Effect of a broad-host range plasmid on growth dynamics of Escherichia coli and Pseudomonas putida

Host-plasmid interactions were studied for the broad-host range plasmid, pTJS26, a derivative of RK2. To isolate host and plasmid contributions to the growth dynamics and plasmid stability, separate experiments were performed with host and recombinant cells for two different gram-negative hosts, Pseudomonas putida and Escherichia coli, at two different temperatures, 30 and 37 degrees C. At the lower temperature (30 degrees C) the growth kinetics were not affected by the plasmid, but plasmid instability was observed. At the higher temperature (37 degrees C) growth rates and yields were lower than that for the hosts, but the plasmid was stable. This behavior can be explained by a combination of two phenomena. First, the copy number control mechanism may be temperature sensitive and, second, plasmid segregation may be inefficient. For both E. coli and P. putida the growth dynamics of the recombinant system was dictated by the presence of the plasmid.     

Results of combined therapy in patients with nonseminomatous testicular tumors

The results of multidrug therapy of 44 male patients with non-seminomatous testicular tumours are discussed. The diagnosed tumours were of all stages of the clinical advances and were treated with combined chemotherapy (surgery and PVP regimen). Thirty two patients (73%) are followed up between 7 and 103 months and survived, complete remission is noted in 29 patients (66%) including 6 patients who survived over 5 years. Symptoms of the tumour are found in 3 patients. Twelve patients (27%) died. The treatment did not produce life-threatening complications. The obtained results have been compared with those reported by other authors.     

Larval and adult morphology ofCamallanus anabantis Pearse, 1933 andC. kulasirii (Yeh, 1960) (Nematoda: Camallanidae) from freshwater fishes,with notes on the validity of some related forms

Larvae and adults ofCamallanus anabantis andC. kulasirii, recovered from the West Bengali freshwater fishes,Anabas testudineus andOphicephalus punctatus, respectively, are described on the basis of detailed morphological studies under the light microscope. Larval forms collected fromA. testudineus are deemed to be of the third and fourth stages when compared with those from experimental studies of the life cycle ofC. anabantis. Moreover, the present fourth stage female larvae are similar to the females ofC. pearsei, both morphologically and metrically.C. pearsei is, therefore, believed to represent the fourth stage female larvae ofC. anabantis. Similarly, adult males and females recovered fromO. punctatus closely resembleC. kulasirii andC. fernandoi, respectively. The larval forms from this host are fourth stage and can be distinguished as males and females, but both possess a buccal capsule bearing beaded longitudinal ridges similar to that of adult males. The late fourth stage (just prior to the final moult) female larva is, however, found to possess a buccal capsule transitional between that of the adult male and female and also betweenC. kulasirii andC. fernandoi. C. fernandoi is, therefore, presumed to represent the females ofC. kulasirii. However,C. pearsei andC. fernandoi are regarded, for the present, asspecies inquirendae.     

Mitochondrial genome in animal cells. Structure, organization, and evolution

In the past decade, the development of new DNA, RNA, and protein technologies has greatly incremented the knowledge about the organization and expression of mitochondrial DNA. The complete base sequence of mitochondrial DNA of several animals is known and many data are rapidly accumulating on the mitochondrial genomes of other systems. Here we discuss the results so far obtained that disclosed unexpected features of mitochondrial genetics. Furthermore, mitochondrial DNA has become established as a powerful tool for evolutionary studies in animals. Evidences are presented demonstrating that the evolution of mitochondrial DNA has proceeded in different ways in the various taxonomic groups. Data on heteroplasmic animals, which demonstrate the rapid evolution of mitochondrial DNA, are also presented.     

Immunophenotyping of acute myeloid leukaemia: relevance of analysing different lineage-associated markers

The immunophenotype of 135 previously untreated patients with FAB defined acute myeloid leukaemia (AML) was studied at diagnosis. The panel of reagents included monoclonal antibodies (MoAb) recognising myeloid-associated determinants (CD11, CD13, CD14, CD33 and others) as well as MoAb directed towards lymphoid antigens (CD7, CD10, CD19) and TdT. The results indicate that CD13 and/or CD33 are consistently expressed in AML and only rarely in ALL blasts (131/135 + ve cases, versus 4/130 in ALL). Lymphoid antigen expression was rarely detected when CD10 and CD19 were investigated in AML (0.9% and 2% + ve cases, respectively), whereas significant positivities were found for TdT and CD7 (20% and 10% respectively). Concerning FAB subtypes, two new MoAb (LAM3 and LAM7) proved very useful in the specific recognition of AML with monocytic features. The phenotype CD13+ and/or CD33+, CD9+, HLA-DR- was found to be almost exclusive for M3 AML. The response to induction chemotherapy was analysed in CD7+ and in TdT+ patients. In the latter group a statistically significant lower response rate was found with respect to TdT-ve-AML patients.     

Influence of lactate on isoproterenol-induced lipolysis and beta-adrenoceptors distribution in human fat cells

The influence of lactate on human adipocytes lipolysis and the possible relationship between lactate-induced metabolic effects and beta-adrenoceptor binding sites were investigated. beta-sites were identified in membranes with (125I)-cyanopindolol and in intact cells with (125I)-cyanopindolol and (3H)-CGP 12177. Lactate reduced isoproterenol-induced lipolysis in a dose-response fashion and such inhibition became significant only at 16 mmol/l lactate. Exposure of human fat cells to 16 mmol/l lactate significantly reduced beta-adrenoceptors density on crude membranes. When the binding assay was performed on intact cells using (125I)-cyanopindolol at 37 degrees C, the radioligand identified the same number of receptors, regardless of the presence of lactate in the preincubation medium. When (3H)-CGP 12177 was used, it bound to about 35% less receptors in lactate pre-treated cells than in control. Seemingly, at 37 degrees C, because of its lipophilicity, (125I)-cyanopindolol can cross the plasma membrane and bind to intracellular sites whereas, (3H)-CGP 1277, due to its hydrophilicity, identifies surface receptors only. Thus, the present in vitro study provides evidence that high levels of lactate, similar to the concentrations usually achieved in overt lactic acidosis, are able per se to inhibit human lipolysis and to redistribute beta-adrenoceptors from cell surface to a domain not accessible to hydrophilic ligands.     

Stirred fluidised-bed reactor developed for low-density biocatalyst supports

Summary A new type of multistage fluidised-bed reactor was constructed to avoid the fluidisation irregularities by slow stirring of the bed. Aminoacylase immobilized on a polyacrylamide type bead polymer was used as biocatalyst for resolution of racemic amino acids. The efficiency was considerably higher than that of a traditional packed-bed reactor.     

A new technique for the treatment of palpebral bags

A new technique for the treatment of palpebral bags is presented. The technique consists of returning fat to the orbital cavity and retaining it by means of a continuous suture (with nonabsorbable filament) of the capsulopalpebral fascia to the periosteum of the lower orbital rim. The anatomic basis for the technique, after examination of the relevant literature and dissection on fresh cadavers, is analyzed. The procedure followed and results obtained are described in detail. Evaluation of the results suggests to the authors that this might be the method to be applied in the majority of patients.     

Microspectrofluorimetric analysis of the formaldehyde-induced fluorophores of 5-hydroxytryptamine and dopamine in intrapulmonary neuroepithelial bodies after administration ofl-hydroxytryptophan andl-DOPA

Summary To demonstrate the intracellular store of 5-hydroxytryptamine and dopamine in pulmonary neuroepithelial bodies of the neonatal rabbit after treatment with the corresponding amino-acid precursorsl-5-hydroxytryptophan orl-3,4-dihydroxyphenylalanine, formaldehyde-induced flourescence in combination with microspectrofluorimetric analysis has been used. Emission spectra and excitation spectra in an extended wavelength range from 240 to 460 nm, the displacement of excitation peaks after exposure to hydrochloric acid vapour, and calculation of peak ratio values 410/260, 380/320, 320/260 for phenylethylamine fluorophores and 385/315 for indolylethylamine fluorphores were performed. Thus, the presence of 5-hydroxytryptamine without occurrence of 5-hydroxytryptophan was demonstrated in pulmonary neuroepithelial bodies after administration of the corresponding biological precursor, while dopamine combined with 5-hydroxytryptamine were clearly revealed after administration ofl-3,4-dihydroxyphenylalanine. The rate of photodecomposition always corroborated these findings.Dedicated to Prefessor Dr. T.H. Schiebler on the occasion of his 65th birthdaySupported by grant nr. 3.0059.81 (to D.W.S.) from the Fund for Medical Scientific Research (Belgium)