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A training sample of 14 sequences of E. coli, each 70 or 69 base pairs long, with their (relative) promoter strengths given by Deuschle et al. (1986, EMBO J. 5, 2987-2994), is used to find a relation between the occurrence frequencies of the two consensus patterns and the promoter strength. The approach is restricted to an analysis of purine and pyrimidine organization using the theory of stationary alternate Markov chains of first order. Further, it is shown, both empirically by regression analysis, and by a Markov-chain-oriented statistical analysis, that the difference of occurrence frequencies and the determinant of transition matrix, which was introduced in a previous paper (Recknagel et al., 1993, J. theor. Biol. 162, 75-80), are equivalent measures with respect to the task of promoter strength prediction. An empirical regression equation is given that allows the promoter strength to be forecast from the occurrence frequencies of the canonical hexamers in the consensus boxes. Three E. coli promoters of an examination sample, separated from the training sample, are classified this way, in agreement with the experimental findings.

A training sample (taken offhand) of 14 promoter sequences, 70 or 69 base pairs in length each, with their (relative) promoter strengths given by Deuschle et al. (1986), is used to find a relation between some sequence characteristics and the promoter strength. The analysis is based on the doublet frequencies of purines and pyrimidines in the promoter sequence under study.

Based upon the above results, Dey-Wash was found to be an effective wound cleansing agent. In over 80% of the patients, it cleansed the wound of exudate and debris in less than half the time and without the effort or abundance of materials required by the bulb syringe method. While splashback was reported by some nurses, this risk exists for all methods. Inservicing and protocols based on universal precautions will decrease the occurrence of this problem. As nurses became familiar with the proper angle and distance for applying the Dey-Wash, the problem of splashback became more manageable. Effective wound cleansing is a very necessary step in the wound healing process. The literature clearly describes the importance and variances of this practice in terms of different methodologies. Knowledge of the current literature concerning wound irrigation can guide nursing actions. Emphasis continues to be placed on appropriate utilization of nursing time and materials. Therefore, it is in the best interest of healthcare providers to evaluate new materials and methods in order to maximize care and facilitate optimum wound healing.

We have studied the catalysis of the exchange of the hydrogen-bonded NH-N protons of the short DNA helix (d-CCAAGCTTGG)2 by phosphate addition. The NH exchange rates were monitored by the line widths of the corresponding NH resonances in the 1H nmr spectra. The exchange catalyst phosphate is most effective on the exchange rate of the terminal CG1 base pairs. However, all internal base pairs are also moderately affected by phosphate which suggests an exchange mechanism governed by a fast equilibrium between opened and closed states of the duplex. Within the limits of error the same effectiveness of phosphate on the exchange rate of all internal NH-N protons has been observed. With the exception of the terminal base pairs, no sequence and/or position specificity of the exchange rates of the NH-N protons of the base pairs has been found.

The purpose of this study was to compare the effectiveness of ankle taping and a semirigid orthosis in providing ankle support before and after exercise. Twenty-two ankles were treated with ankle taping (treatment I) and a semirigid orthoses (treatment 11). Passive ankle inversion-eversion was measured on a Cybex IP prior to application of the treatment, following application of the treatment, and following a brief period of exercise. A two-way ANOVA and post hoc Tukey analyses indicated that post-application and post-exercise ankle motion was significantly less than preapplication motion for both treatment groups. However, inversion motion postexercise was significantly greater than pre-exercise motion for the taping condition, and the semirigid orthosis limited ankle motion significantly more than the taping treatment following exercise. The results suggest that a semirigid orthosis similar to the one tested in this study may be more effective in preventing ankle sprain njuries than athletic tape J Orthop Sports Phys Ther 1987;9(1):33-39.

According to the acid-growth hypothesis, auxin-induced secretion of hydrogen ions activate "wall loosening" enzymes that change the rheological properties of the cell wall. The wall loosening process may yield monosaccharides by the enzymic cleavage of load-bearing polysaccharides. Our study was initiated to determine the metabolic fate of such sugars when released from the major hemicellulosic polysaccharides of the cell walls of Zea mays coleoptiles.Excised coleoptile sections accumulated radioactive glucose, arabinose, and xylose supplied in an incubation medium, and the radioactivity from these sugars was incorporated into polysaccharides. At least 50% of the radioactivity from glucose accumulated in the soluble neutral sugar fraction regardless of external concentrations. The distribution of radioactivity from xylose into all subcellular fractions was similar to that from glucose, indicating that xylose was converted to glucose before being used by the coleoptile. IAA increased the incorporation of glucose into cell wall polysaccharide and neutral sugar pools when the exogenous concentration was higher than 1 millimolar.Over 80% of the radioactivity from arabinose accumulated by the coleoptile sections was incorporated into soluble and noncellulosic polymers; IAA induced an increase in the incorporation of arabinose into noncellulosic polymers by 22%. Accumulation of radioactivity from arabinose into polysaccharide was enhanced by IAA at concentrations of exogenous arabinose up to 33 millimolar.IAA promoted the incorporation of both arabinose and glucose into cell wall polysaccharides even when elongation was inhibited by CaCl(2), indicating that the influence of IAA was not a consequence of the growth response.

A simple, inexpensive method for the injection of crystalline horseradish peroxidase is described that uses glass micropipettes. The horseradish peroxidase is expelled from the pipette by a fine wire inserted to the end of the pipette. A clay plug prevents diffusion of HRP during the needle's descent. The technique enables the investigator to reliably produce small, densely labeled injection sites with minimal diffusion. Both the retrograde and anterograde transport seen using this method compare favorably with that seen using iontophoretic or pressure injection methods.

A systematic analysis of the distribution of cells containing horseradish peroxidase (HRP) end-product following HRP injections in the bed nucleus of the stria terminalis (BNST) revealed a topographic distribution of input from the amygdala. The appearance of HRP cells in the medial amygdaloid nucleus was associated with HRP injections in all parts of the amygdala except its most lateral portion. Injections of HRP confined to the anterolateral portion of the BNST resulted in extensive HRP labeling of cells in the basolateral amygdala, the central nucleus, and the amygdala hippocampal area. Labeling of the amygdala hippocampal area was also associated with HRP injections in the caudodorsal BNST or the supracommissural portion of the stria terminalis. Injections that labeled the commissural division of the stria terminalis produced labeling of cells in the anterior basolateral amygdala and in the nucleus of the lateral olfactory tract. The cortical and basomedial amygdaloid nuclei appear to project only weakly to the BNST. Several other regions that provide afferents to the BNST are described although their input is minor relative to that of the amygdala.

Kindling of seizures with stimulation of anterior neocortex was examined in control rats and in Brattleboro rats deficient in arginine-vasopressin (AVP). There were no significant differences between control rats, homozygous Brattleboro rats, and heterozygous Brattleboro rats in the rate and pattern of kindling of generalized seizures. Thus AVP is not critically involved in anterior neocortical kindling.