Changes of free, soluble conjugated and bound polyamine titers of jojoba explants under sodium chloride salinity in vitro

Jojoba (Simmondsia chinensis L.) single node explants were cultured in a basal medium supplemented with 17.8 microM 6-benzyladenine and four levels of sodium chloride concentration (0, 56.41, 112.82 and 169.23 mM). The free, the soluble conjugated and the insoluble bound forms of polyamines (PAs) (putrescine (Put), spermidine (Spd) and spermine (Spm)) were determined monthly during a 3-month proliferation stage. Free Put and Spd were found in higher levels in the control treatment, while Spm content was higher in the salt treatments. All soluble conjugated PAs were found to be in lower concentrations in explants growing on medium supplemented with salt, while the opposite was true for the insoluble bound PAs. It appeared that certain PAs and PAs forms could play a significant role in the adaptation mechanism of jojoba under saline conditions.     

Telephonocardiography: The Transmission of Electrocardiograms by Telephone

Transmission of electrocardiograms via long-distance telephone (telephonocardiography) from Wingham to London, Ontario, was carried out over a period of three months, early in 1964. The object of this study was to ascertain whether or not the telephonocardiogram was a practical and reliable method of interpreting such tracings for outlying areas. During this period 102 tracings were recorded on 71 patients. Thirty-one (30%) of the tracings were normal and 71 (70%) abnormal. Analysis of the clinical data revealed that the telephonocardiogram was extremely valuable in five of 71 patients (7%) and was also of considerable value to 11 other patients (16%) in providing immediate diagnosis and thereby indicating definite treatment. The trial also demonstrated that the method was practical, accurate and easy to perform.     

The capacity for organic synthesis in cells of successive developmental stages

Summary Synthesis of organic matter was studied on synchronized suspensions of the green high-temperature alga, Chlorella 7-11-05, in regard to the composition of the suspending fluid and the developmental status of cells. Rates of synthetic activity were determined as changes in optical density of algal populations. The validity of this technique was substantiated by special parallel measurements of changes in optical density, dry weight, and chlorophyll content of algal suspensions.It was found that cells of earlier developmental stages generally possess a higher capacity for organic synthesis than cells approaching the end of the life cycle. Earlier reports on the decline in the photosynthetic capacity toward cell division, observed in such nitrogen-free media as phosphate, bicarbonate, and Warburg's No. 9 buffers, were thus substantiated by observations on the decline in organic synthesis in the course of cell development recorded in the same three, as well as in several other, nitrogen-free and nitrogen-containing media.Vacillation of metabolic activity throughout the life cycle and in the course of measurements during one experiment was discussed, and a higher reliability of the time-course curves as compared with a set of data obtained for short-time intervals was ascertained. The regular sequence of changes in synthetic activity in the course of cell development was ascribed to the regularity of changes in the rates of the anabolic and catabolic moieties of the metabolic turnover.     

Characterization of the backbone dynamics of an anti-digoxin antibody VL domain by inverse detected 1H–15N NMR: Comparisons with X-ray data for the Fab

The dynamic behavior of the polypeptide backbone of a recombinant anti-digoxin antibody V_L domain has been characterized by measurements of ¹⁵N T₁ and T₂ relaxation times, ¹H–¹⁵N NOE values, and ¹H–²H exchange rates. These data were acquired with 2D inverse detected heteronuclear ¹H–¹⁵N NMR methods. The relaxation data are interpreted in terms of model free spectral density functions and exchange contributions to transverse relaxation rates R₂ (= 1/T₂). All characterized residues display low-amplitude picosecond timescale librational motions. Fifteen residues undergo conformational changes on the nanosecond timescale, and 24 residues have significant R₂ exchange contributions, which reflect motions on the microsecond to millisecond timescale. For several residues, microsecond to millisecond motions of nearby aromatic rings are postulated to account for some or all of their observed R₂ exchange contributions. The measured ¹H–²H exchange rates are correlated with hydrogen bonding patterns and distances from the solvent accessible surface. The degree of local flexibility indicated by the NMR measurements is compared to crystallographic B-factors derived from X-ray analyses of the native Fab and the Fab/digoxin complex. In general, both the NMR and X-ray data indicate enhanced flexibility in the turns, hypervariable loops, and portions of β-strands A, B, and G. However, on a residue-specific level, correlations among the various NMR data, and between the NMR and X-ray data, are often absent. This is attributed to the different dynamic processes and environments that influence the various observables. The combined data indicate that certain regions of the V_L domain, including the three hypervariable loops, undergo dynamic changes upon V_L:V_H association and/ or complexation with digoxin. Overall, the 26–10 V_L domain exhibits relatively low flexibility on the ps–ns timescale. The possible functional consequences of this result are considered. © 1993 Wiley-Liss, Inc.     

Nucleolar organizer regions in the normal,hyperplastic and carcinomatous epithelium of endometrium

A silver colloid technique to identify nucleolar organizer region associated protein (AGNORs) has been applied to paraffin sections in a total of 43 endometrial hyperplasias (24 adenomatous and 19 adenocystic) 26 endometrial carcinomas and 22 normal endometria (11 of proliferative and 11 of secretory phase). A morphometric analysis of highly magnified photographic images of AGNORs in light microscopic preparations was performed. Malignant tumor cells showed significantly higher AGNOR numbers, maximum diameter and mean area compared with normal and hyperplastic endometrium, with the exception of adenocystic hyperplasia whose D_max and mean area were significantly larger. Regarding the distribution pattern of AGNOR dots in the cases studied, it was found that normal and hyperplastic endometrium had a mainly clustered distribution while endometrial adenocarcinomas revealed a scattered one. The significant differences observed in the number of AGNORs, their size and mean area between benign and malignant endometrial epithelia suggest that the AG-NOR staining technique is of diagnostic importance in distinguishing between these two groups.