Inactivation of the postural asymmetry factor at the stage of compensation for the postural disorder induced by unilateral removal of the motor area

The peptide nature of the posture asymmetry factor (PAF) produced in the brain after unilateral removal of the motor region of the neocortex was established. The inactivation of PAF activity in the brain toward the end of the third week after the removal is due to PAF inactivation by the endogenous factor absent from the intact brain. The molecular weight of the inactivation factor exceeds 5.0 kD that makes it possible to separate it from the PAF by gel filtration on Sephadex G-25. The correlation was marked between the increasing activity of the PAF inactivation factor and the recovery of the initial symmetric functioning of the spinal centers during three weeks after unilateral damage to the CNS.     

The reduction of alpha-ketocarboxylic acids and alpha-dicarbonyl compounds with titanium(III) chloride

Thirteen model alpha-ketocarboxylic acids and alpha-dicarbonyl compounds have been observed to be reduced by titanium(III) chloride. The products of these reactions were shown by melting (boiling) points, mixed melting points, derivatives, refractive indices, infrared, and NMR comparisons with authentic compounds or literature information to be the corresponding alpha-hydroxycarboxylic acids or alpha-hydroxyketones.     

Cyclic nucleotide alterations in mixed leukocyte reaction: a preliminary report

Endogenous cyclic adenosine and guanosine monophosphate (cAMP, cGMP) levels were studied in human peripheral blood lymphocytes during mixed leukocyte reactions (MLR). cAMP level was consistently elevated in one-way MLR, with good correlation to 3H-thymidine uptake in these reactions. In contrast, cGMP level was practically unchanged. Irradiation of reacting cell populations resulted in inhibition of cyclic nucleotide phosphodiesterase (PDE) activity. These results suggest that metabolic alterations in cAMP may be associated with immune reactions of cellular recognition.     

A comparison of the respiratory chain in particles from Paracoccus denitrificans and bovine heart mitochondria by EPR spectroscopy

A study is presented on the EPR characteristics of the paramagnetic groups in the respiratory chain present in membrane particles of Paracoccus denitrificans, the respiratory system of which is very similar to that in submitochondrial particles from beef heart. All paramagnetic prosthetic groups of the mitochondrial system are also found in the bacterial plasma membrane. Their properties suggest that the respiratory groups are embedded in very similar protein environments in the two systems.     

Artifacts following gold staining of Western-blotted membranes

Protein samples were separated by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis, electrophoretically transferred to nitrocellulose membranes, and stained with colloidal gold. Three artifact bands appeared demonstrating apparent molecular weights of 58,000, 63,000, and 65,000. The appearance of these bands was due to oxidized dithiothreitol used to denature the proteins prior to electrophoresis. The appearance of the artifact bands could be avoided by the addition of excess iodoacetamide to the denatured protein sample and by limiting staining time to 1.5 h at 13 V/cm.     

Effects of troponin I phosphorylation on conformational exchange in the regulatory domain of cardiac troponin C.

Conformational exchange has been demonstrated within the regulatory domain of calcium-saturated cardiac troponin C when bound to the NH2-terminal domain of cardiac troponin I-(1-80), and cardiac troponin I-(1-80)DD, having serine residues 23 and 24 mutated to aspartate to mimic the phosphorylated form of the protein. Binding of cardiac troponin I-(1-80) decreases conformational exchange for residues 29, 32, and 34. Comparison of average transverse cross correlation rates show that both the NH2- and COOH-terminal domains of cardiac troponin C tumble with similar correlation times when bound to cardiac troponin I-(1-80). In contrast, the NH2- and COOH-terminal domains in free cardiac troponin C and cardiac troponin C bound cardiac troponin I-(1-80)DD tumble independently. These results suggest that the nonphosphorylated cardiac specific NH2 terminus of cardiac troponin I interacts with the NH2-terminal domain of cardiac troponin C.     

Marine incursions,cryptic species and ecological diversification in Amazonia: the biogeographic history of the croaker genus Plagioscion (Sciaenidae)

Aim We propose a phylogenetic hypothesis for the marine‐derived sciaenid genus Plagioscion in the context of geomorphology and adaptation to freshwaters of South America, and assess the extent to which contemporary freshwater hydrochemical gradients influence diversification within a widely distributed Plagioscion species, Plagioscion squamosissimus. Location Amazon Basin and South America. Methods Using nuclear and mitochondrial DNA sequence data, phylogenetic analyses were conducted on the five nominal Plagioscion species, together with representatives from Pachyurus and Pachypops, using character and model‐based methods. Genealogical relationships and population genetic structure of 152 P. squamosissimus specimens sampled from the five major rivers and three hydrochemical settings/‘colours’ (i.e. white, black and clear water) of the Amazon Basin were assessed. Results Phylogenetic analyses support the monophyly of Plagioscion in South America and identify two putative cryptic species of Plagioscion. Divergence estimates suggest that the Plagioscion ancestor invaded South America via a northern route during the late Oligocene to early Miocene. Within P. squamosissimus a strong association of haplotype and water colour was observed, together with significant population structure detected between water colours. Main conclusions Our analyses of Plagioscion are consistent with a biogeographic scenario of early Miocene marine incursions into South America. Based on our phylogenetic results, the fossil record, geomorphological history and distributional data of extant Plagioscion species, we propose that marine incursions into western Venezuela between the late Oligocene and early Miocene were responsible for the adaptation to freshwaters in Plagioscion species. Following the termination of the marine incursions during the late Miocene and the establishment of the modern Amazon River, Plagioscion experienced a rapid diversification. Plagioscion squamosissimus arose during that time. The formation of the Amazon River probably facilitated population and range expansions for this species. Further, the large‐scale hydrochemical gradients within the Amazon Basin appear to be acting as ecological barriers maintaining population discontinuities in P. squamosissimus even in the face of gene flow. Our results highlight the importance of divergent natural selection through time in the generation and maintenance of sciaenid diversity in Amazonia.     

A preliminary investigation of prediction of mean arterial pressure after self-regulatory treatments.

This study investigated the ability of pretreatment variables from three different domains (social-demographic, psychological, and psychophysiological) to predict posttreatment mean arterial pressure (MAP) for 59 unmedicated males with mild hypertension who were participating in a cross-cultural (USA-USSR) comparison of autogenic training and thermal biofeedback to a self-relaxation control. The overall multiple regression equation consisted of two variables and indicated that higher diastolic blood pressures during a cold pressor task were predictive of greater MAP reductions while higher scores on the Irritability subscale of the Buss-Durkee Hostility Scale were predictive of less MAP reductions. Suggestions for future research in this area are provided.