Spirocyclic Dipeptides of 1-Amino-1-cyclohexanecarboxylic Acid

1994 ◽  
Vol 59 (1) ◽  
pp. 195-202 ◽  
Author(s):  
Jarmila Vinšová ◽  
Karel Kosař ◽  
Evžen Kasafírek
Keyword(s):  
General Formula ◽  
Screening Test ◽  
Methyl Esters ◽  
Cyclohexanecarboxylic Acid ◽  
Cyclobutanecarboxylic Acid

Spirocyclic cyclodipeptides with 1-amino-1-cyclohexanecarboxylic acid of the general formula cyclo(-Ach-A-), where A is Gly, L-Ala, D-Ala, L-Val, D-Val, L-Leu, D-Leu, D-Pgl, L-Phe or D-Phe, have been prepared by cyclization of the corresponding linear dipeptide methyl esters. The peptides cyclo(-L- or D-Ala-Ach-), cyclo(-L-Val-Ach-) and cyclo(-D-Leu-Ach-) show higher activity in the Chick Embryotoxicity Screening Test when compared with derivatives containing 1-amino-1-cyclopentanecarboxylic acid or 1-amino-1-cyclobutanecarboxylic acid.

Synthesis and Antiproliferative Activity of Spirocyclic Cyclodipeptides, Derivatives of 1-Amino-1-cyclobutanecarboxylic Acid

1993 ◽  
Vol 58 (12) ◽  
pp. 2987-2993 ◽  
Author(s):  
Jarmila Vinšová ◽  
Karel Kosař ◽  
Evžen Kasafírek
Keyword(s):  
Amino Acids ◽  
General Formula ◽  
Antiproliferative Activity ◽  
Screening Test ◽  
Proliferative Activity ◽  
Lower Activity ◽  
Chick Embryos ◽  
Cyclobutanecarboxylic Acid ◽  
Derivatives Of

A series of chiral spirocyclic cyclodipeptides of the general formula I was synthesized; the aim was to determine how the substitution of cyclobutane for cyclopentane in cyclo(-alanyl-1-amino-1-cyclopentanecarbonyl-) would influence the inhibition of the proliferative activity of the caudal morphogenic system (CMS) of Chick embryos. Spirocyclic cyclodipeptides Ia - Il were obtained by cyclization of linear dipeptides IIa - IIf, prepared by condensation of protected amino acids by DCCI method. The inhibition was investigated by the Chick Embryotoxicity Screening Test. The results show generally lower activity in the tested series, as compared with derivatives containing 1-amino-1-cyclopentanecarboxylic acid.

Calcium ion imaging in plant cells

1993 ◽  
Vol 51 ◽  
pp. 132-133
Author(s):  
Peter K. Hepler ◽  
Dale A. Callaham
Keyword(s):  
Plant Cell Wall ◽  
Cytoplasmic Membrane ◽  
Fluorescent Dyes ◽  
Free Acid ◽  
Methyl Esters ◽  
Free Calcium ◽  
Local Concentration ◽  
Ion Imaging ◽  
Membrane Compartments ◽  
Free Acid Form

Calcium ions (Ca) participate in many signal transduction processes, and for that reason it is important to determine where these ions are located within the living cell, and when and to what extent they change their local concentration. Of the different Ca-specific indicators, the fluorescent dyes, developed by Grynkiewicz et al. (1), have proved most efficacious, however, their use on plants has met with several problems (2). First, the dyes as acetoxy-methyl esters are often cleaved by extracellular esterases in the plant cell wall, and thus they do not enter the cell. Second, if the dye crosses the plasma membrane it may continue into non-cytoplasmic membrane compartments. Third, even if cleaved by esterases in the cytoplasm, or introduced as the free acid into the cytoplasmic compartment, the dyes often become quickly sequestered into vacuoles and organelles, or extruded from the cell. Finally, the free acid form of the dye readily complexes with proteins reducing its ability to detect free calcium. All these problems lead to an erroneous measurement of calcium (2).

Short-Form Application of the Screening Test of Spanish Grammar and the Northwestern Syntax Screening Test to Latino Children

1978 ◽  
Vol 9 (4) ◽  
pp. 220-235
Author(s):  
David L. Ratusnik ◽  
Carol Melnick Ratusnik ◽  
Karen Sattinger
Keyword(s):  
New York ◽  
Case Studies ◽  
Metropolitan Area ◽  
Screening Test ◽  
Normative Data ◽  
Short Form ◽  
Latino Children ◽  
Data Application ◽  
York Metropolitan Area ◽  
Multiple Regression Technique

Short-form versions of the Screening Test of Spanish Grammar (Toronto, 1973) and the Northwestern Syntax Screening Test (Lee, 1971) were devised for use with bilingual Latino children while preserving the original normative data. Application of a multiple regression technique to data collected on 60 lower social status Latino children (four years and six months to seven years and one month) from Spanish Harlem and Yonkers, New York, yielded a small but powerful set of predictor items from the Spanish and English tests. Clinicians may make rapid and accurate predictions of STSG or NSST total screening scores from administration of substantially shortened versions of the instruments. Case studies of Latino children from Chicago and Miami serve to cross-validate the procedure outside the New York metropolitan area.

Computer-Managed Screening for Communication Disorders

1984 ◽  
Vol 15 (2) ◽  
pp. 66-69 ◽  
Author(s):  
James L. Fitch ◽  
Linda Allen Davis ◽  
W. Bryce Evans ◽  
Daniel E. Sellers
Keyword(s):  
Satisfactory Agreement ◽  
Screening Test ◽  
Communication Disorders ◽  
Pencil And Paper ◽  
Paper Format

Fifty children were administered a screening test for communication disorders under two conditions. Under one condition graduate clinicians administered the test in the traditional pencil and paper format. Under the second condition nonprofessionals administered a computer-managed version of the same test. It was found that the computer-managed screening test yielded satisfactory agreement for the language sections. The results of the articulation section of the screening test were ambiguous.

Rapid screening test for porphyrinuria

1970 ◽  
Vol 102 (2) ◽  
pp. 237-237
Author(s):  
R. M. McDonald
Keyword(s):  
Screening Test ◽  
Rapid Screening ◽  
Rapid Screening Test

New CF Screening Test Offers Greater Accuracy

2005 ◽  
Vol 38 (16) ◽  
pp. 37
Author(s):  
CHRISTINE KILGORE
Keyword(s):  
Screening Test
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