ISOTOPIC AND CHEMICAL EVIDENCE FOR THREE ACCRETIONARY MAGMATIC ARCS (1.79-1.42 GA) IN THE SW AMAZON CRATON, MATO GROSSO STATE, BRAZIL

2000 ◽  
Vol 30 (1) ◽  
pp. 099-101 ◽  
Author(s):  
MAURO CESAR GERALDES ◽  
WILSON TEIXEIRA ◽  
WILLIAM RANDALL VAN SCHMUS
Author(s):  
Steven M. Le Vine ◽  
David L. Wetzel

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.


Author(s):  
H.B. Pollard ◽  
C.E. Creutz ◽  
C.J. Pazoles ◽  
J.H. Scott

Exocytosis is a general concept describing secretion of enzymes, hormones and transmitters that are otherwise sequestered in intracellular granules. Chemical evidence for this concept was first gathered from studies on chromaffin cells in perfused adrenal glands, in which it was found that granule contents, including both large protein and small molecules such as adrenaline and ATP, were released together while the granule membrane was retained in the cell. A number of exhaustive reviews of this early work have been published and are summarized in Reference 1. The critical experiments demonstrating the importance of extracellular calcium for exocytosis per se were also first performed in this system (2,3), further indicating the substantial service given by chromaffin cells to those interested in secretory phenomena over the years.


Author(s):  
T.R. FELDPAUSCH, ◽  
E. GANDINI, ◽  
S. JIRKA, ◽  
J. LEHMANN, ◽  
A.J. MCDONALD, ◽  
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2020 ◽  
Vol 45 (2) ◽  
pp. 340-348
Author(s):  
James Lucas da Costa-Lima ◽  
Earl Celestino de Oliveira Chagas

Abstract—A synopsis of Dicliptera (Acanthaceae) for Brazil is presented. Six species are recognized: Dicliptera ciliaris, D. sexangularis, and D. squarrosa, widely distributed in South America; D. purpurascens, which ranges from the North Region of Brazil (in the state of Acre) to eastern Bolivia; D. gracilirama, a new species from the Atlantic Forest of northeastern Brazil; and D. granchaquenha, a new species recorded in dry and semideciduous forests in Bolivia and western Brazil, in the state of Mato Grosso do Sul. Furthermore, we propose new synonyms and designate lectotypes for eleven names. An identification key to the six accepted Dicliptera species in Brazil is provided.


Author(s):  
F. PERBONI ◽  
Carla Regina de Souza FIGUEIREDO ◽  
A. MARQUES ◽  
A. N. MILITÃO ◽  
C. N. JESUS ◽  
...  

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