Molecular cloning of cDNA coding for human preprourokinase

A cDNA library was constructed in pBR322 from 18S to 20S mRNA that was extracted from human kidney cells, fractionated on oligo(dT)-cellulose column and sucrose-density gradient, and confirmed for urokinase production in Xenopus laevis oocytes. The Escherichia coli RR1 transformants were hybridized to synthetic oligonucleotide probe prepared according to the known amino acid sequence, Glu 73 to Glu 77 of human urinary urokinase chain B. The entire cloned cDNA covers a 2250-bp region, wherein the 1293-bp sequence codes for preprourokinase consisting of 431 amino acids, with the first 20 residues being a signal peptide. The 5'-untranslated region is at least 80 bp long and the 3'-untranslated region is longer than 850 bp.     

Biofeedback control of migraine headaches: A comparison of two approaches

In order to assess the relative effectiveness of finger warming and temporal blood volume pulse reduction biofeedback in the treatment of migraine, 22 female migraine patients were assigned to one of three experimental conditions: temporal artery constriction feedback, finger temperature feedback, or waiting list. Biofeedback training consisted of 12 sessions over a 6-week period. All patients completed 5 weeks of daily self-monitoring of headache activity (frequency, duration, and intensity) and medication before and after treatment. Treatment credibility was assessed at the end of Sessions 1, 6, and 12. Results showed that temporal constriction and finger temperature biofeedback were equally effective in controlling migraine headaches and produced greater benefits than the waiting list condition. Power analyses indicated that very large sample sizes would have been required to detect any significant differences between the two treatment groups. No significant relationships were found between levels of therapeutic gains and levels of thermal or blood volume pulse self-regulation skills. Likewise, treatment outcome was not found to be related to treatment credibility. Further analyses revealed that changes in headache activity and medication were associated with changes in vasomotor variability. Because blood volume pulse variability was not significantly affected by biofeedback training, questions about its role in the therapeutic mechanism are raised.This research was supported in part by grants from the Quebec Ministry of Education and the Quebec Ministery of Social Affairs to the first author, and an award from the Medical Research Council of Canada to the second author. The authors are indebted to Drs. Frank Andrasik, Howard Barbaree, Edward Blanchard, Martin Ford, and Patrick McGrath, as well as to two anonymous reviewers, for their helpful comments on an earlier draft of this paper.     

Floristic groups and plant communities of southeastern Santa Fe,Argentina

This paper is a survey of the vegetation of the southeastern departments in the Province of Santa Fe (Argentina). The vegetation was analyzed following Braun-Blanquet's approach modified by Mueller-Dombois & Ellenberg (1974). The most relevant species of the region were placed in 25 groups according to their requirements or general behaviour. Most of the communities are herbaceous, and apart from the woody and some other miscellaneous ones they were grouped into three ecologically and floristically defined sets. The first set, the Stipa grasslands and related communities, which are characterized by the more or less abundant presence of Stipa hyalina, Stipa neesiana and Stipa papposa, comprises five different communities. The second, the halophilous communities, comprises five communities, the two Spartina ssp. grasslands, the halophilous prairies of Distichlis spicata, the short sedge Scirpus americanus communities and the ‘pela-dales’. The third, the hygrophilous communities, comprises nine communities which are not so well defined as the ones in the other sets. Besides, two further communities have been included, the Paspalum quadrifarium and the Melica macra tall grasslands.     

Mefluidide-chlorsulfuron-2,4-D surfactant combinations for roadside vegetation management

Using a combination of a primary growth retardant, mefluidide, a synergistic additive, chlorsulfuron, a detergent to enhance penetration (X-77), and a herbicide, 2,4-D, to provide for control of broadleaf weeds, full-season management of bluegrass (Poa pratensis L.)—tall fescue (Festuca arundinaceae Schreb.) mixtures along roadsides has been achieved. A single spray application is made in the spring, and no additional herbicide applications or mechanical mowing are needed. The treatment is effective with greater than 90% control of fescue seed heads. Those few seed heads that do form remain short. It is economical. The costs of materials and application are equal to or less than the cost of a single mowing cycle. The treatment is environmentally safe when applied in early spring before most agricultural crops have been planted. The effectiveness and low cost of the combination derive from laboratory and greenhouse observations that various materials, herein referred to as additives, often only weakly effective as growth retardants themselves, will interact synergistically with mefluidide to provide overall treatment effectiveness at application rates that are economical. Using this principle, a combination suitable for roadside vegetation management was devised, field-tested for 2 years under actual use conditions, and found to be effective for full-season vegetation management of mixed bluegrass—tall fescue turf to permit considerable cost savings when compared to three-cycle mechanical mowing.     

An improved method to isolate lichen algae by gel filtration

Photobiont cells of the lichen Evernia prunastri have completely been separated from their fungal partner by filtration through a bed of Sepharose 2B. Both mannitol and ribitol have been quantified by gas-liquid chromatography in the different steps of the isolation procedure. Absence of mannitol, which is exclusively produced by the mycobiont, has been used as the best probe to monitor isolation.     

Actinomycin D and cycloheximide actions on activity of some intestinal enzymes of adult hamster

Actinomycin D, at a dose of 0.25 micrograms/g body wt, produced slight increases in intestinal enzymatic activity on hamsters. At a high dose (1.5 micrograms/g body wt), actinomycin D produced inhibition of lactase activity, whereas maltase, sucrase and alkaline phosphatase activity decreased in males and increased in females. Cycloheximide (1.5 micrograms/g body wt), produced no changes in enzymatic activity. In the male and female hamster, the different actions of the antibiotic can be explained by the variations in the cortisol release produced by stress.     

Immunoelectrophoretic approach to the metabolic regulation of glutamine synthetase in Rhodopseudomonas capsulata E1F1: role of glutamine

Anti-glutamine synthetase serum was raised in rabbits by injecting purified glutamine synthetase (GS) of the phototrophic bacterium Rhodopseudomonas capsulata E1F1. The antibodies were purified to monospecificity by immunoaffinity chromatography in GS-sepharose gel. These anti-GS antibodies were used to measure the antigen levels in crude extracts from bacteria, grown phototrophically with dinitrogen, nitrate, nitrite, ammonia, glutamate, glutamine or alanine as nitrogen sources. The amount of GS detected by rocket immunoelectrophoresis was proportional to Mn²⁺-dependent transferase activity measured in the crude extracts. Addition of GS inhibitor l-methionine-d,l-sulfoximine (MSX) to the actively growing cells promoted increased antigen levels, that were not found in the presence of glutamine or chloramphenicol. The ammonia-induced decrease in GS relative levels was reverted by MSX. GS levels remained constant when phototrophically growing cells were kept in the dark.Abbreviations GS glutamine synthetase - MOPS 2-(N-morpholine) propane sulfonate - MSX l-methionine-d,l-sulfoximine     

Time course localization of immunoglobulin M monoclonal antibody and its fragments in leukemic tumor-bearing mice

Summary In vivo localization of a mouse monoclonal antibody (F₂-10.23 IgM) binding leukemic L 1210 cells was studied in DBA/2 mice bearing an L 1210 tumor. F(ab)₂ fragments were prepared and their specific binding to L 1210 cells was analyzed by flow cytofluorometry. Radiolocalization studies were performed by using ¹²⁵I- or ¹³¹I-labeled IgM monoclonal antibody or its F(ab')₂ fragments to ascertain their capacity to visualize the L 1210 tumor. F(ab)₂ fragments were cleared more rapidly than the whole IgM; the clearance was as fast in healthy as in tumor-bearing mice. The tumor-to-muscle ratio observed 24 h after injection of ¹²⁵I-radiolabeled F(ab)₂ fragments and ¹²⁵I-radiolabeled IgM was 10; the radioactivity level in the blood with F(ab)₂ fragments was lower than with IgM, and so -camera imaging was workable with F(ab)₂ fragments without background substraction. The tumor localization was studied over a period of 5 days by recording the distribution of the iodinated fragments in the tumor-bearing leg compared with that in the normal leg, and by computer analysis of the region of interest. F(ab)₂ fragments gave better results than intact IgM in tumor visualization. Nevertheless, the rapid clearance of this antibody or its F(ab)₂ fragments make them hardly suitable as carriers of toxic drugs. Abbreviations used are: MEM Minimum essential medium; SDS sodium dodecylsulfate; PAGE polyacrylamide gel electrophoresis     

Physiological characteristics of the tympanic organ in noctuoid moths

Summary The tympanic organ ofSpodoptera frugiperda, Mocis latipes, Erebus odorata (Noctuidae) andMaenas jussiae (Arctiidae) was stimulated with acoustic stimuli of 20 kHz, 45 ms and 5 s duration, and intensities ranging from 30 to 100 dB. The electric activity of the auditory receptors was recorded at the tympanic nerve with a stainless steel hook electrode. In all of these moth species there is an intensity range (ca. 20 dB) in which the response of each auditory receptor (A₁ and A₂ cells) to 45 ms pulses varies in a linear relation to the logarithm of stimulus intensity. For intensities higher than this value, depending on the species and the cell analysed, the spike discharge may continue to increase, may saturate or may diminish (Fig. 2). InE. odorata andM. latipes the A₁-cell response shows a decrease for stimulus intensities higher than 30 dB above the threshold. In the former species there is a statistically significant linear relation between the A₂-cell response and the decrease of the A₁-cell response, but this is not the case inM. latipes (Fig. 3). The similarity of the responses ofE. odorata to those described inEmpyreuma pugione (Coro and Pérez 1984) suggest that also in this noctuid species one may assume that the A₂ cell inhibits the A₁ receptor. In all of these moth species there is a maximum firing rate of the auditory cells at the beginning of the response to pure tones of 5 s and an exponential decrease of their discharge frequency with the course of time (Fig. 5). The analysed species differ in the adaptation rates of their auditory receptors. In all of these species the A₂ cell adapts more rapidly than the A₁ cell. In most of these species the stimulus intensity influences the adaptation rate of the auditory receptors (Fig. 7). These results are compared with data obtained by other authors, and it is concluded that there are more interspecific differences in the physiological characteristics of the auditory receptors in noctuoid species than those reported so far.Abbreviation AP action potential