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A cDNA clone encoding part of chymotrypsin B was isolated from a cDNA library prepared from rat pancreatic mRNA and used as a probe to isolate the chymotrypsin B gene. The nucleotide sequence of this gene is presented. The 4709-base pair transcribed portion of the isolated gene was inferred from the cDNA and gene sequence, and the 5' border was determined by primer extension on pancreatic polyadenylated RNA. The coding portion of the gene is interrupted by six introns. The active site residues His 57, Asp 102, and Ser 195 are encoded by separate exons. Moreover, two regions of the enzyme which form the substrate-binding pocket are also encoded by separate exons. Thus, the substrate specificity and catalytic activity of the enzyme are produced by joining several exons encoding protein segments that are intrinsically catalytically inactive. The number and location of the intron/exon junctions of the chymotrypsin gene as compared to those of other serine protease genes, as well as the location of the genes on separate chromosomes, suggest that the duplication that resulted in the formation of the chymotrypsin gene was an ancient evolutionary event.

A new synthesis of 9-hydroxy- and 9-(alkylamino)thiazolo[5,4-b]quinolines by cyclization of 4-(ethoxycarbonyl)-5-(arylamino)thiazoles and 5-(arylamino)-4-carbamoylthiazoles, respectively, is described. In vitro cytotoxicity of a large number of derivatives of these compounds has been tested against several cell lines. The highest activities observed are associated with the presence of a 2-[[(N,N-diethylamino)ethyl]amino] substituent at C-2 and a fluorine atom at the C-7 position of the tricyclic planar heteroaromatic framework. Three structural features seem to be essential for antitumor activities:  a positive charge density at carbon C-7, a side chain at position C-2 or C-9 of the thiazoloquinoline skeleton with two basic nitrogens and a pKa value of 7.5−10 in the most basic center, and a conformational flexibility of this basic side chain. These structural requirements must be simultaneously satisfied in order to ensure a significant antitumor activity.

Rat carboxypeptidase A cDNA clones have been isolated from a cDNA library prepared from pancreatic mRNA. An almost complete mRNA sequence has been deduced that predicts a polypeptide having 78% amino acid sequence homology with bovine carboxypeptidase A. The amino acid sequence of the activation and signal peptides of the carboxypeptidase A precursor were inferred from the nucleotide sequence. The cDNA was used as a probe to identify DNA fragments containing carboxypeptidase A sequences in a bacteriophage lambda library of rat genomic DNA. Heteroduplexes revealed that the DNA coding sequence occupies 5.5 kilobases and is interrupted by nine intervening sequences. The nucleotide sequence of the 5' end of the gene and the adjacent flanking region provides information on the site of initiation of transcription and the putative control regions. There is no evident relationship between the localization of intervening sequences in the gene and functional/structural domains of the protein.

A lack of factor VIII:C, manifested as a bleeding disorder due to the absence of clot formation, is known as hemophilia A, an X chromosome-linked inherited disease afflicting 1-2 males/10,000. To determine the minimum functional domain(s) essential for factor VIII:C activity, we have expressed the amino-terminal (92-kDa) and carboxyl-terminal (80-kDa) proteolytic cleavage products as individual, secreted polypeptides in monkey cells without the 909-residue central region. We have found that neither terminal domain alone is able to promote coagulation in factor VIII:C-deficient plasma. However, when the 92- and 80-kDa peptides are co-expressed, clotting activity is readily detected. Thus, these two chains alone constitute an active or activatable complex. The central domain is required neither for activity nor for the assembly of an active complex from two chains expressed in trans. These results suggest that a truncated derivative of factor VIII:C may be useful in coagulation therapy.

Reproductive studies usually utilizes measurement of progesterone in various fluids such as plasma, serum or milk. It has been shown that progesterone concentrations in bovine whole blood decrease proportionally to: i) the time elapsed between the collection of the sample and the separation of plasma or serum from the erythrocytes and ii) the temperature of storage during this period (Breuel et al,1988, Pulido et al.1991). The addition of anticoagulants cause a more rapid decline in progesterone concentrations (Wiseman et al.1982). In equine, porcine and canine blood samples storage time and temperature has a negligible effect on progesterone concentrations (Wiseman et al.1982; Oltner & Edqvist1982). Cordero et al.(1991) working with llama and alpaca whole blood, treated with EDTA as anticoagulant, reported a slight progesterone metabolization in alpaca plasma, but not in llama plasma.

AbstractThis paper reviews the use of video games for measuring intelligence differences and reports two studies analyzing the relationship between intelligence and performance on a leisure video game. In the first study, the main focus was to design an Intelligence Test using puzzles from the video game. Forty-seven young participants played “Professor Layton and the curious village”® for a maximum of 15 hours and completed a set of intelligence standardized tests. Results show that the time required for completing the game interacts with intelligence differences: the higher the intelligence, the lower the time (d= .91). Furthermore, a set of 41 puzzles showed excellent psychometric properties. The second study, done seven years later, confirmed the previous findings. We finally discuss the pros and cons of video games as tools for measuring cognitive abilities with commercial video games, underscoring that psychologists must develop their own intelligence video games and delineate their key features for the measurement devices of next generation.

AbstractThe purpose of this study was to analyze the DiViSA’s predictive validity in school-age children. To do so, two groups of school-age children were compared: one with low school achievement (N= 1,174), and one with typical development (N= 1,426). The obtained results show that: (1) in all grades, children with poor school performance exhibited lower levels of attention and task organization, greater hastiness, and made more commission errors; (2) the combination of variables that best differentiated between groups was not the same in all grades; (3) level of organization improved with age in the low-school-achievement group, and did not in the typical-development group; (4) the data regarding sensitivity (81% to 93%) and specificity (79% to 90%), for the first time computed for each grade separately, support the test’s predictive validity in the grades we evaluated. The discussion focuses on the DiViSA test’s usefulness in diagnosing attention problems. It is the first computerized test to include separate scores for: (a) how children complete the task (organization) and (2) the source of their errors (distraction or hastiness).

The addition of either the alkaline enolates of the glycinates 1or their naked enolates to electron defficient alkynes allows for the synthesis of substituted ( Z)- α, β-didehydroglutamic acid derivatives 7viaa Michael addition /1,3-prototropic rearrangement sequence.