scholarly journals Relationship Between Ricinus Communis Agglutinin-1 Binding and Nucleolar Organizer Regions in Human Gliomas

1993 ◽  
Vol 33 (6) ◽  
pp. 345-349
Author(s):  
Shuji NIIKAWA ◽  
Akira HARA ◽  
Shinichi SHIRAKAMI ◽  
Wei ZHANG ◽  
Noboru SAKAI ◽  
...  
1992 ◽  
Vol 572 (1-2) ◽  
pp. 314-318 ◽  
Author(s):  
Koji Kajiwara ◽  
Tetsuji Orita ◽  
Takafumi Nishizaki ◽  
Toshifumi Kamiryo ◽  
Hisato Nakayama ◽  
...  

Neurosurgery ◽  
1991 ◽  
pp. 211 ◽  
Author(s):  
A Hara ◽  
N Sakai ◽  
H Yamada ◽  
H Hirayama ◽  
T Tanaka ◽  
...  

Neurosurgery ◽  
1991 ◽  
Vol 29 (2) ◽  
pp. 211-215 ◽  
Author(s):  
Akira Hara ◽  
Noboru Sakai ◽  
Hiromu Yamada ◽  
Hiroshi Hirayama ◽  
Takuji Tanaka ◽  
...  

Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
L. Stefaneanu ◽  
N. Losinski

Human pituitary corticotropins have unique morphologic markers: bundles of type-1 filaments, measuring approximately 70 A in width and representing cytokeratin. The extreme ring-like accumulation of type-1 filaments, known as Crooke's hyalinization, signals functional suppression of the corticotropins and occurs in endogenous and exogenous glucocorticoid excess, caused by ACTH-secreting pituitary adenoma, glucocorticoid secreting adrenocortical tumor, ectopic ACTH-syndrome and administration of pharmacologic doses of glucocorticoids. Cells of autonomous corticotroph adenomas usually do not show Crooke's hyalin change. A minority of these tumors, however, retains sensitivity to the negative feed-back effect of elevated blood glucocorticoid levels and display typical Crooke’s change.In the present study pituitary corticotropins in various phases of Crooke's hyalinization were investigated in patients with glucocorticoid excess of various origin, applying histology, immunocytochemistry, count of argyrophilic nucleolar organizer regions (AgNOR), and transmission electron microscopy.


2006 ◽  
Vol 73 ◽  
pp. 77-84 ◽  
Author(s):  
Jane E. Wright ◽  
Christine Mais ◽  
José-Luis Prieto ◽  
Brian McStay

Human ribosomal genes are located in NORs (nucleolar organizer regions) on the short arms of acrocentric chromosomes. During metaphase, previously active NORs appear as prominent chromosomal features termed secondary constrictions, which are achromatic in chromosome banding and positive in silver staining. The architectural RNA polymerase I transcription factor UBF (upstream binding factor) binds extensively across the ribosomal gene repeat throughout the cell cycle. Evidence that UBF underpins NOR structure is provided by an examination of cell lines in which large arrays of a heterologous UBF binding sequences are integrated at ectopic sites on human chromosomes. These arrays efficiently recruit UBF even to sites outside the nucleolus, and during metaphase form novel silver-stainable secondary constrictions, termed pseudo-NORs, that are morphologically similar to NORs.


1988 ◽  
Vol 60 (02) ◽  
pp. 182-187 ◽  
Author(s):  
Morio Aihara ◽  
Ken Tamura ◽  
Ryuko Kawarada ◽  
Keizou Okawa ◽  
Yutaka Yoshida

SummaryThe adhesion of human fixed washed platelets (FWP) to collagen was decreased after treatment with Serratia marcescens protease (SP), which removed 95% of the glycocalicin from platelet membrane glycoprotein (GP) lb. However, the diminished adhesion of SP treated FWP to collagen could still be increased in the presence of purified von Willebrand factor (vWF). This ability of vWF to increase FWP adhesion to collagen is defined as collagen cofactor (CCo). The adhesion of FWP to collagen was not affected by a monoclonal antibody (MAb) to GP Ilb/IIIa (10E5), that inhibits ADP and collagen induced platelet aggregation. On the other hand, it was decreased by 50% by a MAb to GP lb (6D1), that inhibits ristocetin induced platelet aggregation. Adhesion of FWP in buffer to collagen was completely inhibited by Ricinus communis agglutinin I or concanavalin A, while Lens culinalis agglutinin and wheat germ agglutinin showed 50% inhibition. The FWP adhesion to collagen in the presence of vWF (normal plasma) was unaffected by MAbs to GP Ilb/IIIa (10E5, P2, HPL1) but was decreased to 32-38% by MAbs to GP lb (6D1, AN51, HPL11). A MAb to vWF (CLB-RAg 35), that inhibits ristocetin induced binding of vWF to platelets, decreased the CCo of normal plasma by 70%. The MAb, CLB-RAg 201, that inhibits the binding of vWF to collagen, completely inhibited the CCo of normal plasma. In conclusion, our data suggest that (1) GP lb has a partial role in FWP adhesion to collagen; (2) the binding of vWF to collagen is required for the expression of CCo; (3) CCo is partly mediated through GP lb; but (4) other platelet membrane protein(s) besides GP lb or GP Ilb/IIIa must also be involved in FWP-vWF-collagen interactions.


1986 ◽  
Vol 55 (03) ◽  
pp. 338-341 ◽  
Author(s):  
H Takahashi ◽  
W Tatewaki ◽  
M Hanano ◽  
R Nagayama ◽  
A Shibata

SummaryPlatelet-type von Willebrand’s disease (vWD) is a bleeding disorder characterized by a heightened interaction between platelets and von Willebrand factor (vWF) as the result of an intrinsic platelet abnormality (probably in GPIb). Platelet aggregability was nearly normal in response to thrombin, wheat germ agglutinin and Ricinus communis agglutinin in this disorder. Unmodified platelets showed no aggregation upon the addition of peanut agglutinin. Partially purified human vWF induced little aggregation of washed patient platelets, but the aggregation was greatly enhanced in the presence of plasma devoid of vWF. Monoclonal antibodies directed against GPIb and GPIIb/IIIa as well as EDTA completely inhibited vWF-induced aggregation. These results indicate that human vWF induces aggregation of platelet-type vWD platelets in the presence of divalent cations and some plasma cofactor(s), and that both GPIb and GPIIb/IIIa are involved in this aggregation.


1984 ◽  
Vol 26 (5) ◽  
pp. 564-568 ◽  
Author(s):  
Orlando Moreira-Filho ◽  
Luiz Antonio Carlos Bertollo ◽  
Pedro Manoel Galetti Jr.

Nucleolar organizer regions (NORs) were studied in mitotic chromosomes of four species of fish of family Parodontidae: Parodon tortuosus, Apareiodon affinis, Apareiodon ibitiensis, and Apareiodon piracicabae. All four species exhibited only a single nucleolar chromosome pair in their karyotypes. Intraspecific differences were observed in the size of these chromosomes; however, these were not very clear for A. affinis and A. piracicabae, Apareiodon piracicabae exhibited two clearly visible NORs in each of the nucleolar chromosomes, which was the only configuration practically found in this species. This trait therefore predominates in a homozygous condition in the population investigated. Regions of constitutive heterochromatin adjacent to the two NORs were detected. Possible mechanisms that may have originated the two NORs are discussed.Key words: nucleolar organizing regions, fish.


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