1201
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Abstract
Over a 2-year period we have identified pollen grains from 48 families of grasses, as well as mould spores and mite particles during air sampling in Guangxi Province. The major aeroallergens were Artemisia, Moraceae and Euophoribiacea, and the spores of Aspergillus, Penicillinum, Cephalosporium and Helminthosporium. Mites were probably also one of the major outdoor aeroallergens. Our investigations also included inspection of the vegetation of the geographical area involved, as well as skin testing on 774 subjects using extracts of 37 aeroallergens. We believe that this work has provided fundamental information on seasonal allergy in Southern China and South-east Asia.
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1202
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Chen K, Liang P, Yu M, Chang ST. A New Double-Stranded RNA Virus from Volvariella volvacea. Mycologia 1988. [DOI: 10.2307/3807565] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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1203
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Haldar P, Chen K, Maheswaran B, Roig-Janicki A, Jaggi NK, Markiewicz RS, Giessen BC. Bulk Superconductivity at 122 K in T1(Ba,Ca)
2
Ca
3
Cu
4
O
10.5+δ
with Four Consecutive Copper Layers. Science 1988; 241:1198-200. [PMID: 17740783 DOI: 10.1126/science.241.4870.1198] [Citation(s) in RCA: 95] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The observed increase of superconducting transition temperature (T(c)) with the number of copper oxide planes continues in the four-[CuO(2)](-2) layer (single TI layer) oxide superconductor, which has been prepared with > 80% purity and was magnetically aligned for crystallographic identification. A master scaling curve is proposed, which ties together the T(c)'s of virtually all known Bi and Tl oxide superconductors, and shows that the Tl(Bi) layers play an essential role in the superconductivity. publication 350 of the Barnett Institute.
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1204
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Chen K, Morse PD, Swartz HM. Kinetics of enzyme-mediated reduction of lipid soluble nitroxide spin labels by living cells. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 943:477-84. [PMID: 3415989 DOI: 10.1016/0005-2736(88)90380-x] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Nitroxide spin labels can be reduced to the corresponding hydroxylamines in cells. The selective action of inhibitors, and thermal and chemical inactivation demonstrate that the reduction of nitroxides in cells is an enzymatic or enzyme-mediated process. The kinetics of reduction of doxylstearates are affected by the position of the doxyl moiety along the stearic acid chain. The doxyl moiety of 5-doxylstearate is close to the membrane surface, and its reduction is first order with respect to the nitroxide, whereas the doxyl moieties of 10- and 12-doxylstearate are in the membrane hydrocarbon region and their reduction is a zero-order process. The reduction of 16-doxylstearate which usually has a mixture of first- and zero-order kinetics becomes zero order with addition of an extracellular broadening agent, potassium trioxalatochromiate(III). These results suggest that the rate of reduction of doxyl moieties is controlled by their accessibility to reducing equivalents, i.e., the rate-limiting step for the reduction of the doxyl moiety deep in the membrane is the diffusion of reducing equivalents within or into the membrane. The reduction of doxylstearates in cells is inhibited by rotenone but not antimycin A, cyanide, propyl gallate or SKF-525A. It appears that the reduction of doxylstearates takes place at the level of the ubiquinone in the respiratory chain in mitochondria in these cells.
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1205
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Chen K, Swartz HM. Oxidation of hydroxylamines to nitroxide spin labels in living cells. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 970:270-7. [PMID: 2840969 DOI: 10.1016/0167-4889(88)90126-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In the presence of oxygen, cells can oxidize hydroxylamines, which are the products of the reduction of nitroxides in cells, back to nitroxides. Lipid-soluble hydroxylamines are oxidized much more rapidly than water-soluble ones, and most of this oxidation is inactivated by heat or trichloroacetic acid, indicating that the principal mechanism is enzyme-linked. The rates of oxidation of some lipophilic hydroxylamines are comparable to the rates of reduction of the corresponding nitroxides. Hydroxylamines formed by reduction of aqueous soluble nitroxides are not oxidized by cells, except for slight oxidation of some pyrrolidine derivatives. The latter is due to autoxidation. The kinetics of oxidation of reduced lipid-soluble nitroxides are all first-order with respect to hydroxylamines, regardless of the position of the nitroxide group along the carbon backbone, indicating that the oxidation occurs within the membrane. The oxidation of hydroxylamines in cells in inhibited by cyanide but not by antimycin A or SKF-525A. We also describe an effective method to oxidize hydroxylamines and follow this reaction; the method is based on the use of perdeuterated [15N]Tempone.
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1206
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Boscia R, Chen K, Johnson JT, Whiteside TL. Evaluation of therapeutic potential of interleukin 2-expanded tumor-infiltrating lymphocytes in squamous cell carcinoma of the head and neck. Ann Otol Rhinol Laryngol 1988; 97:414-21. [PMID: 3261562 DOI: 10.1177/000348948809700416] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Tumor-infiltrating lymphocytes (TILs) were isolated from surgically excised squamous cell carcinoma of the head and neck. Immunohistology showed that the tumor was infiltrated by T-lymphocytes, many of which were activated as judged by the expression of the following surface antigens: HLA-DR, transferrin receptor, and receptors for interleukin 2 (IL2). Fresh TILs were unable to lyse natural killer cell (NK)-resistant and NK-sensitive tumor cell targets in chromium-release cytotoxicity assays. Tumor-infiltrating lymphocytes as well as autologous peripheral blood lymphocytes were cultured in media containing natural IL-2. Tumor-infiltrating lymphocytes proliferated better than autologous peripheral blood lymphocytes and exhibited sustained growth and antitumor effector function in long-term cultures. The IL2-expanded culture of TILs contained mostly CD8+ (suppressor/cytotoxic) T-lymphocytes with the morphology characteristic of lymphokine-activated killer cells. The ability to expand TILs with augmented antitumor activity in long-term cultures indicates that these cells could be therapeutically useful. Potential application of human TILs to adoptive immunotherapy of squamous cell carcinoma of the head and neck is discussed, and recent advances in immunotherapy with IL2-activated TILs are reviewed.
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1207
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Markiewicz RS, Chen K, Jaggi N. Effective-medium theory of an anisotropic conductor applied to the high-Tc superconductors. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 37:9336-9342. [PMID: 9944319 DOI: 10.1103/physrevb.37.9336] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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1208
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Zeimer RC, Chen K. Comparison of a noninvasive measurement of optic nervehead mechanical compliance with an invasive method. Invest Ophthalmol Vis Sci 1987; 28:1735-9. [PMID: 2958427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
We have postulated that abnormal mechanical support of the optic nervehead at the level of the lamina cribrosa could be the precursor of glaucomatous damage. Recent studies have shown deformations of the lamina cribrosa to be among the earliest changes in glaucoma. To evaluate the support of the nervehead, we have developed a noninvasive optical method to measure the optic nervehead compliance, namely, the displacement of the optic nervehead induced by an artificial increase in intraocular pressure. To test the validity of the method, we have compared noninvasive measurements obtained in post-mortem enucleated human eyes with those recorded using an invasive technique. Both methods had a reproducibility better than 6 microns and induced no damage capable of interfering with the results. The displacements measured by both methods were similar, thus indicating that our optical method is capable of measuring bulk motion of the optic nervehead. Our results were identical with those obtained by other authors using a third method. The data obtained also established the normal range of optic nervehead displacements induced by a range of intraocular pressure increments.
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1209
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He Y, Chen K, Jayaprakash C. Numerical study of the critical properties of an irreversible cellular automaton. PHYSICAL REVIEW. A, GENERAL PHYSICS 1987; 36:2999-3002. [PMID: 9899212 DOI: 10.1103/physreva.36.2999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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1210
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Swartz HM, Chen K, Roth JA. Further evidence that the pigment in the Dubin-Johnson syndrome is not melanin. PIGMENT CELL RESEARCH 1987; 1:69-75. [PMID: 2853343 DOI: 10.1111/j.1600-0749.1987.tb00392.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The pigment in the Dubin-Johnson syndrome (DJS) is shown unequivocally not to be a typical melanin or closely related polymer. In electron spin resonance (ESR) studies of DJS pigment from a hepatoma, it is shown that, unlike true melanins, the pigment associated with the DJS syndrome has no free radical in the absence of light. Exposure to even low levels of visible light over a broad frequency range induces a free radical in the DJS pigment. Previous studies did not appreciate the sensitivity to light of this pigment and therefore erroneously concluded that the DJS pigment had a permanent free radical. The light induced ESR signal in DJS tissue has spectroscopic properties that differ significantly from any known melanins. The pigment is not extracted by lipophilic solvents and is centrifuged down at 50,000g, but not at 5,000g.
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1211
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Chen K. [[Age composition and population cycles]]. IN'GU MUNJE NONJIP = JOURNAL OF POPULATION STUDIES 1987:15-28. [PMID: 12222471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The author attempts to correlate the endogenous population cycle with changes in age composition by examining population trends in Taiwan. "It is argued that while the size of parental cohort is related to the size of offspring cohort by the renewal process, fluctuations in size are correspondingly transmitted and averaged time after time." The concepts of population cycles as a key factor in population change is also examined. (SUMMARY IN ENG)
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1212
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Chen K, Jayaprakash C, Krishna-Murthy HR. Spatial correlations around a Kondo impurity. PHYSICAL REVIEW LETTERS 1987; 58:929-932. [PMID: 10035075 DOI: 10.1103/physrevlett.58.929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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1213
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Cox RA, Chen K, Coykendall AL, Wesbecher P, Herson VC. Fatal infection in neonates of 26 weeks' gestation due to Streptococcus milleri: report of two cases. J Clin Pathol 1987; 40:190-3. [PMID: 3818983 PMCID: PMC1140866 DOI: 10.1136/jcp.40.2.190] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Fatal sepsis due to a particular biotype of Streptococcus milleri occurred in two neonates born at 26 weeks' gestation. The clinical importance of this biotype in association with premature labour and neonatal sepsis is discussed.
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1214
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Stumpf WE, Sar M, Chen K, Morin J, DeLuca HF. Sertoli cells in the testis and epithelium of the ductuli efferentes are targets for 3H 1,25 (OH)2 vitamin D3. An autoradiographic study. Cell Tissue Res 1987; 247:453-5. [PMID: 3815485 DOI: 10.1007/bf00218327] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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1215
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Chen K, Demetris AJ, VanThiel DH, Whiteside TL. Double immunoenzyme staining method for analysis of tissue and blood lymphocyte subsets with monoclonal antibodies. J Transl Med 1987; 56:114-9. [PMID: 3099082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Double immunoenzymatic method for sequential staining with two different monoclonal murine antibodies and two different enzymes was shown to be useful in defining hematopoietic cell subpopulations in human tissues and blood. The method allows for the identification, localization, and enumeration in the same section of distinct cell populations. Air-dried smears of cell mixtures can be stained. The optimal sequence of enzymes/substrates was: horseradish peroxidase/3-amino-9-ethylcarbazole followed by the alkaline phosphatase-anti-alkaline phosphatase complex/naphthol AS-MX phosphate. Red-and blue-colored reaction products are easy to view in a light microscope. Combinations of two different mouse monoclonal antibodies or of a mouse monoclonal antibody and polyclonal antiserum made in rabbits or goats can be sequentially applied to the same section or smear thus facilitating a definition of the distribution of two cell populations reactive with these antibodies. The relative distribution patterns in tissues of cells bearing distinctive antigens are important in studies of cellular differentiation and of human pathogenetic processes including neoplasia and transplant rejection.
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1216
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Abstract
A 25-year-old housewife presented with an 8-month history of epigastric pain, vomiting and weight loss. This was found to be due to sarcoidosis of the stomach. Her condition improved remarkably on steroids.
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1217
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Flowers RS, Eckner K, Gabis DA, Robison BJ, Mattingly JA, Silliker JH, Bailey J, Bednar A, Chen K, Cirigliano M, Coschigano M, Deibel K, DonLevy T, Eckner K, Elliott P, Erickson J, Feldsworth M, Fenlon M, Finn S, Fischer G, Gaugert A, Givich K, Graham C, Guarino P, Hall P, Humber J, Jogan M, Jones W, Jost K, Koenig E, Lenovich L, Loudermilk L, Lynn T, Magno E, Miklovic G, Nemeth B, Nolan D, Posey D, Rasilewicz C, Risty N, Roberts B, Rogers J, Romick T, Clair VS, Sakai H, Schwenger K, Smittle D, Smoeger D, Sparks D, Sveum W, Tong M, Tremont D, Trailer J, Arman TV, Way JV, Wagner C, Wagner D, Walsh K, Worley N, Zari C. Enzyme Immunoassay for Detection of Salmonella in Foods: Collaborative Study. J AOAC Int 1986. [DOI: 10.1093/jaoac/69.5.786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
A collaborative study was performed in 25 laboratories to validate an enzyme immunoassay (EIA) procedure utilizing 2 specific monoclonal antibodies for rapid detection of Salmonella in foods. The EIA was compared with the standard culture procedure for detection of Salmonella in 6 food types: ground black pepper, soy isolate, dried whole eggs, milk chocolate, nonfat dry milk, and raw deboned turkey, Uninoculated and inoculated samples were included in each food group analyzed, with the exception of poultry which was naturally contaminated. There was no significant difference in the productivity of the EIA and culture procedures at the 5% level for any of the 6 foods. The enzyme immunoassay screening method has been adopted official first action.
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1218
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Chen K, Wang T, Chen W. [Causes and consequences of population change in Taiwan]. IN'GU MUNJE NONJIP = JOURNAL OF POPULATION STUDIES 1986:1-23. [PMID: 12222423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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1219
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Abstract
The rate of reduction of nitroxides is shown to be more rapid in hypoxic cells. The rate of reduction and the effect of hypoxia on the reduction rate vary for different nitroxides. These findings indicate that it may be feasible to develop in vivo NMR contrast agents that selectively will indicate areas of hypoxia and thereby aid in the detection of disease processes such as neoplasia, ischemia, and inflammation.
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1220
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Horowitz P, Matthews BS, Forster J, Linscott I, Teague CC, Chen K, Backus P. Ultranarrowband searches for extraterrestrial intelligence with dedicated signal-processing hardware. ICARUS 1986; 67:525-539. [PMID: 11539670 DOI: 10.1016/0019-1035(86)90129-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Multichannel spectroscopy with millihertz resolution constitutes an attractive strategy for a microwave search for extraterrestrial intelligence (SETI), assuming the transmission of a narrow-band radiofrequency beacon. Such resolution matches the properties of the interstellar medium, and the necessary receiver Doppler corrections provide a high degree of interference rejection. We have constructed a frequency-agile swept receiver with an 8,388,608-channel spectrum analyzer, on-line signal recognition, and multithreshold archiving. A search of 250 Sun-like stars at 1.4 and 2.8 GHz has been carried out with the Arecibo 305-m antenna, and a meridian transit search of the northern sky is in progress at the Harvard-Smithsonian 26-m antenna. Successive spectra of 400 kHz at 0.05 Hz resolution are searched for features characteristic of an intentional narrowband beacon transmission. These spectra are centered on guessable ("magic") frequencies (such as the 21-cm hydrogen hyperfine line), referenced successively to the local standard of rest, the galactic barycenter, and the cosmic blackbody rest frame.
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1221
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Mayberry MJ, Porkolab M, Chen K, Fisher AS, Griffin D, Kaplan RD, Luckhardt SC, Ramos J, Rohatgi R. Frequency scaling of the lower-hybrid-current-drive density limit in tokamak plasmas. PHYSICAL REVIEW LETTERS 1985; 55:829-832. [PMID: 10032458 DOI: 10.1103/physrevlett.55.829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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1222
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Chen K, Zhang JT. A study of aeroallergens in Nanning, Guangxi, China. ANNALS OF ALLERGY 1985; 54:242-4. [PMID: 3977141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
There were 43 families of airborne pollen in Nanning, and the major sensitizing pollens were those of Gramineae, Artemisia (a genus of Compositae), Chenopodiaceae, and Moraceae. It was found that sensitization with pollens of the same genus is similar. This may be helpful in selecting the proper antigen for immunotherapy.
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1223
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Chen K, Wight TN. Proteoglycans in arterial smooth muscle cell cultures: an ultrastructural histochemical analysis. J Histochem Cytochem 1984; 32:347-57. [PMID: 6200530 DOI: 10.1177/32.4.6200530] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The extracellular matrix in cultures of arterial smooth muscle cells has been examined by ultrastructural histochemistry using each of the following cationic dyes: ruthenium red, Alcian blue, acridine orange, and safranin O. All dyes exhibited an affinity for a structural component that was either preserved as a granule with ruthenium red or Alcian blue, or as an extended filament or bottlebrush structure with acridine orange or safranin O. Both granules and filaments were removed when the cultures were pretreated with chondroitinase ABC, an enzyme that degrades the glycosaminoglycan moiety of some proteoglycans. These structural components of the extracellular matrix were not observed when cultures were prepared in the absence of the cationic dyes. Labeling experiments (35S-sulfate) revealed that approximately 40% of the total labeled proteoglycans were lost during routine processing for electron microscopy (i.e., fixation through dehydration). Inclusion of any one of the cationic dyes during fixation reduced the losses to less than 1%. The extended filamentous structure preserved by safranin O and acridine orange resembled the structure of purified proteoglycans prepared from the same cultures and spread on cytochrome c monolayer films. These observations suggest that proteoglycans exist as extended bottlebrush structures within the extracellular matrix, and support the interpretation that the granular deposits observed in the ruthenium red and Alcian blue preparations most likely represent individual proteoglycan monomers that have undergone molecular collapse during processing. In addition, the dyes also exhibited an affinity for chords of fine fibrils that contained small granules and/or filaments. Both the fibrillar material and the associated granular and filamentous structures enmeshed in the fibrils resisted digestion with chondroitinase ABC.
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1224
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Abstract
Aneurysmal bone cysts are uncommon lesions, especially in the ribs. Four patients with aneurysmal bone cysts of the rib are presented and previously reported cases reviewed. A brief discussion of the clinical manifestations, pathology, aetiology, and current treatment of aneurysmal bone cyst is also included.
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1225
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Chen K, Erdman CA, Kennedy MF, Reynolds AB. Particle-Size Distribution in Capacitor Discharge Vaporization of Uranium Dioxide. NUCL SCI ENG 1983. [DOI: 10.13182/nse83-a18649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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