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Summary Using immunocytochemical techniques, we report here direct evidence of kynurenine (Kyn) presence and localization in the lung and brain. Kyn is a metabolite of tryptophan and 5-hydroxytryptophan, produced by indoleamine 2, 3-dioxygenase (IDO). Whereas IDO has been quantitated in tissues from lung, brain, and other organs, Kyn has only been identified in brain (by HPLC), and its specific localization has not been determined.We reacted alternate serial paraffin sections with anti-sera raised in rabbits against a l-Kyn-albumin conjugate, and with anti-5HT (serotonin, 5-hydroxytryptamine), using the PAP method. Kyn-like immunoreactivity in the lung was specifically localized to cells of the bronchiolar epithelium resembling basal cells. Taller epithelial cells in the bronchi and dorsal trachea were likewise positive whereas neuroepithelial bodies were negative. Immunoreactivity in the brain was typically localized to cells localized in the ependyma of the walls of all ventricles, and to nerve fibers. The cellular Kyn-like reactivity was totally separate from that of anti-5HT, the latter uniquely staining argyrophil lung neuroendocrine cells and raphae neurons of the brain. Our findings suggest a route of tryptophan metabolism in the lung and brain alternate to the common pathway leading to 5-hydroxyindoleacetic acid via 5-HT. This route is of physiologic and pathologic significance as many metabolites are pharmacologically active.Supported by the College of Agriculture and Life Sciences, University of Wisconsin-Madison and the Council for Tobacco Research USA, Inc. Grant #1437 相似文献
3.
1. The synthesis of three substrates of alpha-chymotrypsin of closely similar steric requirements but different charge type is reported. 2. The interaction of these compounds [SS-dimethyl-(l-3-carboxymethyl-3-acetamido)propyl sulphonium iodide, l-2-acetamido-5-methylhexanoic acid methyl ester and N-acetyl-l-glutamic acid alpha-methyl ester] with alpha-chymotrypsin has been studied. 3. For the charged substrates, values of k(0) are two orders of magnitude smaller than, and values of K(m) two orders of magnitude larger than, the corresponding values for the uncharged isostere. 4. The results are interpreted in terms of the known specificity of the enzyme, and the relationship between binding and kinetic specificities is discussed. 相似文献
4.
K. Lynette Pearce Dr. Bernard T. Engel John R. Burton 《Applied psychophysiology and biofeedback》1989,14(3):207-217
Fifteen hypertensive patients were recruited from a geriatric medicine clinic for a research project designed to evaluate a Behavioral Stepped-Care treatment program of high blood pressure (HBP). All patients met the selection criteria of the Isolated Systolic Hypertension (ISH) in the Elderly (SHEP) clinical trial. During baseline, subjects recorded BP at home 9 times/day (3 times each, shortly after awakening, during the middle of the day, and within an hour of retiring) for 1 month and mailed that data to us daily. In addition, they came to the clinic weekly and had their BP recorded by a nurse. During treatment 1, systolic (SBP) feedback, they were trained to lower SBP at home using their sphygmomanometers. They also continued to monitor BP and to obtain weekly professional BP readings. During treatment 2 (relaxation), they were trained to relax; they followed the self-administration and data-collection protocol as in treatment 1. Each treatment phase lasted 3 months. Average monthly self-determined BP fell significantly from 166.4/85.8 (SBP/DBP) mm Hg during baseline to 153.3/81.2 by the end of the relaxation phase; average monthly professionally measured BP fell significantly, from 164.7/87.1 to 156.9/81.5. These findings show that a nurse-supervised, patient-administered behavioral treatment program of ISH can yield sustained, significant falls in BP.Ms. Pearce and Dr. Burton were supported in part by the Johns Hopkins Academic Nursing Home Award, PO, AG04402, from the National Institute on Aging. This material was presented in part at the annual meeting of the Gerontological Society of America, November 1988, San Francisco. 相似文献
5.
William J. Schultz Mr. Mark S. Brownfield Gerald P. Kozlowski 《Cell and tissue research》1977,178(1):129-141
Summary Light and electron microscopic examination of choroid plexuses from lateral ventricles of water-deprived and subcutaneously or intravenously vasopressin administered rats reveal morphologic changes typical for vasopressin responsive fluid transporting epithelia during hormonal stimulation. Ultrastructural changes noted in both dehydrated and vasopressin treated animals included: the frequent occurrence of choroidal dark cells, dilatation of the lateral and basal intercellular spaces, increased vacuolization of the apical cytoplasm, and a change in microvillar conformation from the normal clavate type to those with a filiform shape. On the basis of the ultrastructural changes observed it is proposed that the choroid plexus be regarded as a target tissue for vasopressin. These findings indicated that a vasopressinmediated transchoroidal cerebrospinal fluid absorption capability exists.Supported by U.S.P.H.S. Grant HD-08867This work submitted as partial requirement for the Master of Science degree in the Department of Anatomy, Colorado State University 相似文献
6.
Two alpha-L-arabinofuranosidase genes in Arabidopsis thaliana are differentially expressed during vegetative growth and flower development 总被引:1,自引:0,他引:1
Glycosyl hydrolases are important mediators of plant cell wall modification during plant development. These enzymes catalyse the hydrolytic release of specific sugars, such as L-arabinose, from the polysaccharide-rich cell wall matrix. The cloning and expression analysis of two genes, AtASD1 and AtASD2, encoding putative alpha-L-arabinofuranosidases in Arabidopsis thaliana are reported here. AtASD1 and AtASD2 identities were assigned on the basis of homology to plant and microbial family 51 glycoside hydrolases. Using RT-PCR, RNA gel blot analysis and reporter gene expression analysis, AtASD1 and AtASD2 were shown to have different developmental expression profiles. High levels of AtASD1 promoter activity are present in multiple tissues during vegetative and reproductive growth. AtASD1 expression is particularly intense in zones of cell proliferation, the vascular system, developing and regressing floral tissues, and floral abscission zones. By comparison, AtASD2 expression is limited to the vasculature of older root tissue and to some floral organs and floral abscission zones. 相似文献
7.
Jamie Jeffries Wiriya Thongsomboon Joshua Alan Visser Kyle Enriquez Deborah Yager Lynette Cegelski 《Biopolymers》2021,112(1)
Bacterial biofilms are communities of bacteria entangled in a self‐produced extracellular matrix (ECM). Escherichia coli direct the assembly of two insoluble biopolymers, curli amyloid fibers, and phosphoethanolamine (pEtN) cellulose, to build remarkable biofilm architectures. Intense curiosity surrounds how bacteria harness these amyloid‐polysaccharide composites to build biofilms, and how these biopolymers function to benefit bacterial communities. Defining ECM composition involving insoluble polymeric assemblies poses unique challenges to analysis and, thus, to comparing strains with quantitative ECM molecular correlates. In this work, we present results from a sum‐of‐the‐parts 13C solid‐state nuclear magnetic resonance (NMR) analysis to define the curli‐to‐pEtN cellulose ratio in the isolated ECM of the E. coli laboratory K12 strain, AR3110. We compare and contrast the compositional analysis and comprehensive biofilm phenotypes for AR3110 and a well‐studied clinical isolate, UTI89. The ECM isolated from AR3110 contains approximately twice the amount of pEtN cellulose relative to curli content as UTI89, revealing plasticity in matrix assembly principles among strains. The two parent strains and a panel of relevant gene mutants were investigated in three biofilm models, examining: (a) macrocolonies on agar, (b) pellicles at the liquid‐air interface, and (c) biomass accumulation on plastic. We describe the influence of curli, cellulose, and the pEtN modification on biofilm phenotypes with power in the direct comparison of these strains. The results suggest that curli more strongly influence adhesion, while pEtN cellulose drives cohesion. Their individual and combined influence depends on both the biofilm modality (agar, pellicle, or plastic‐associated) and the strain itself. 相似文献
8.
This study investigated how the current economic recession (since December 2007) has affected dog and cat relinquishment, adoption, and euthanasia at the Anti-Cruelty Society animal shelter in Chicago, Illinois. The study compared temporal patterns of the investigated statistics before (2000–2007) the start of the current recession with the patterns after the start of the recession (2008–2010). The results showed that once the guardianship (ownership) of a nonhuman animal had been established, the recession did not greatly affect the owner's decision on relinquishment—except for the relinquishment of senior dogs, which may be associated with increased costs of care. However, an unfavorable economic environment may have reduced adoption of animals. The consequences of a decline in adoptions might be reflected in an increase in the proportion or number of sheltered animals euthanized. This study demonstrated how monitoring changes in temporal patterns in these shelter statistics can help guide animal shelters to better prepare for the current recession. 相似文献
9.
P. L. C. Walker Adele Corrigan Monica Arenas Emilia Escuredo Lynette Fairbanks Anthony Marinaki 《Nucleosides, nucleotides & nucleic acids》2013,32(12):1243-1247
Purine nucleoside phosphorylase (PNPase) deficiency is an autosomal recessive disorder affecting purine degradation and salvage pathways. Clinically, patients typically present with severe immunodeficiency, neurological dysfunction, and autoimmunity. Biochemically, PNPase deficiency may be suspected in the presence of hypouricemia. We report biochemical and genetic data on a cohort of seven patients from six families identified as PNPase deficient. In all patients, inosine, deoxyinosine, guanosine, and deoxyguanosine were elevated in urine, and mutation analysis revealed seven different mutations of which three were novel. The mutation c.770A>G resulted in the substitution p.His257Arg. A second novel mutation c.257A>G (p.His86Arg) was identified in two siblings and a third novel mutation, c.199C>T (p.Arg67X), was found in a 2-year-old female with delayed motor milestones and recurrent respiratory infections. A review of the literature identified 67 cases of PNPase deficiency from 49 families, including the cases from our own laboratory. PNPase deficiency was confirmed in 30 patients by genotyping and 24 disease causing mutations, including the three novel mutations described in this paper, have been reported to date. In five of the seven patients, plasma uric acid was found to be within the pediatric normal range, suggesting that PNPase deficiency should not be ruled out in the absence of hypouricemia. 相似文献
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