The convergent trajectories of bird communities along ecological successions in european forests

Summary There is much more variation in the composition of bird communities in the earlier open and semi-open seral stages of ecological successions in forested landscapes of Europe than later on in preforested and forested climactic stages. The demonstration of this trend is achieved from the study of four habitat gradients, two in the mediterranean region (Provence and Corsica) and two in central Europe (Burgundy, France and Poland). A multivariate analysis has been used to illustrate the dynamics of communities along these succession. Displays of the results in bivariate space as well as an illustration of the distributional profiles of some of the most characteristic species show that: i) there is a discrimination between the two mediterranean gradients and the two medioeuropean ones and ii) each succession starts with a very distinct set of species and then the four gradients regularly converge in the last climactic stage where there is almost no discrimination between communities. These results are discussed in the light of the history of European biotas during the Pleistocene. The reason why there is more variation in species composition in the earlier seral stages than in the later forested stages are discussed according to current theories on the role of habitat selection on speciation processes.     

T-DNA length variability in mannopine hairy root: more than 50 kilobasepairs of pRi T-DNA can integrate in plant cells

Independent carrot (Daucus carota) hairy root lines were established by inoculation of discs taken from the same carrot with Agrobacterium rhizogenes 8196 and A. tumefaciens C58C1(pRi8196) carrying pRi8196. Several lines were compared with respect to T-DNA length. One of them was found to have integrated sequences covering more than 50 kbp of the Ri plasmid     

Use of novel objects to enhance environments of captive chimpanzees

A small group of chimpanzees was allowed to manipulate different quantities of novel objects in order to enhance their captive conditions. This procedure led to a general increase in the manipulation frequency by the apes. It decreased their inactivity and their self-grooming, and almost eliminated the abnormal behaviors displayed by one individual. The distribution of novel objects did not affect the total frequency of social interactions and did not increase the aggressivity of the animals, even though dominant individuals secured most of the objects when only a small number of them were available. Following their familiarization with the novel objects, the chimpanzees' manipulation frequency decreased whereas self-grooming and abnormal behaviors were increased. Suggestions are made on how to maximize the use of a limited bank of toys to occupy captive chimpanzees.     

Absence of Turner stigmata in a 46,XYp-female

A 46,XY female patient with streak gonads and a large deletion of Yp is described. The deletion included the Y chromosomal genes SRY, ZFY, and RPS4Y. The patient did not display any Turner stigmata, such as webbing of the neck, cardiac or other abnormalities. The findings argue against an important role of RPS4Y in the prevention of Turner stigmata in males and are consistent with a role of SRY in testis differentiation in humans.     

Assignment of the gene encoding the catalytic subunit Cβ of CAMP-dependent protein kinase to the p36 band on chromosome

Summary A cDNA for the human catalytic subunit (C) of cAMP-dependent protein kinase (PKA) has been cloned from a testis cDNA library. In the present study, we have determined the chromosomal localization of this gene using a cDNA for C as a probe. Southern blot analysis of genomic DNA from human/mouse cell hybrids revealed that the presence or absence of a 20-kbXbaI fragment, which hybridized with the C probe, was concordant with the presence of human chromosome 1.In situ hybridization to metaphase chromosome confirmed the somatic cell hybrid data and regionally mapped the C gene of PKA to the p36 band on chromosome 1.     

Survey of human and rat microsatellites

Length variations in simple sequence tandem repeats (microsatellite DNA polymorphisms) are finding increasing usage in mammalian genetics. Although every variety of short tandem repeat that has been tested has been shown to exhibit length polymorphisms, little information on the relative abundance of the different repeat motifs has been collected. In this report, summaries of GenBank searches for all possible human and rat microsatellites ranging from mononucleotide to tetranucleotide repeats are presented. In humans, the five most abundant microsatellites with total lengths for the runs of repeats of greater than or equal to 20 nucleotides contained repeat sequences of A, AC, AAAN, AAN, and AG, in order of decreasing abundance, where N is C, G, or T. These five groups comprised about 76% of all microsatellites. Many other human simple sequence repeats were found at low frequency. In the 745 kb of human genomic DNA surveyed, one microsatellite of greater than or equal to 20 nucleotides in length was found, on average, every 6 kb. Only 12% of the human microsatellites had total lengths greater than or equal to 40 nucleotides. Roughly 80% of the A, AAN, and AAAN microsatellites and 50% of the AT microsatellites, but few of the other human microsatellites, were found to be associated with interspersed, repetitive Alu elements. In rats, the five most abundant microsatellites contained AC, AG, A, AAAN, and AAGG sequences, respectively. Rat microsatellites were generally longer than human microsatellites, with 43% of the rat sequences greater than or equal to 40 nucleotides.     

Novel DNA structures resulting from dTam3 excision in tobacco

A Tam3 two-element system has been designed by combining an immobilized Tam3 element with a non-autonomous dTam3 element inserted into the HPT gene. The phenotypic assay employed, restored hygromycin resistance, indicated thattrans-activation of the non-autonomous dTam3 element occurred. Molecular analyses of the excision sites revealed that the ends of the dTam3 element remain in the empty donor sites. The predominant consequence of this type of excision appears to be that excised fragments fail to re-integrate into the tobacco genome. Only one case of dTam3 re-integration could be detected. The ends of this element had been degraded upon integration into the tobacco genome. Either the altered structure of the Tam3 derivatives or tobacco host factors are influencing thetrans-activation of a dTam3 element, resulting in aberrant excision.     

Immobilization of microsomes into alginate beads is a convenient method for producing glucuronides from drugs

Summary The production of glucuronides from drugs by immobilized microsomal uridine diphosphate (UDP)-glucuronosyltransferase has been investigated. Of all the immobilization methods used (covalent binding, adsorption by ionic or hydrophobic interactions), only entrapment of microsomes into alginate beads in the presence of polyethyleneimine was effective in producing high glucuronidation rates, thus leading to the formation of large amounts of metabolites. The performance of the bioreactor was optimized with the drug 3-azido-3-deoxythymidine (AZT), active against the human immunodeficiency virus, as a model substrate of UDP-glucuronosyltransferase. Calcium (12 mm) could optimally improve the stability of microsomes entrapped in alginate beads. Upon immobilization, enzyme activation occurred, leading to a fivefold increase in specific activity. The determination of apparent K _m and V _max revealed that AZT was a better substrate for the immobilized enzyme than free microsomes. The AZT-glucuronide production obtained after 6 h was threefold higher than that observed with free microsomes. This bioreactor was also efficient in production of glucuronides from structurally different compounds such as bilirubin, 4-nitrophenol, clofibric acid, pirprofen, dextrorphan or morphine, the corresponding glucuronide of which possesses pharmacological or toxicological interest. Offprint requests to: J. Magdalou     

Phase I trial of intravenous infusion of ex-vivo-activated autologous blood-derived macrophages in patients with non-small-cell lung cancer: Toxicity and immunomodulatory effects

Summary The purpose of this phase I study was to evaluate the toxicity and biological activity of autologous blood-derived macrophages activated ex-vivo with recombinant human interferon (rhuIFN) [monokine-activated killer (MAK) cells] and administered intravenously to 11 lung cancer patients once a week for 6 consecutive weeks. Peripheral blood monocytes were collected by leukapheresis and then purified by counterflow elutriation. The MAK cells were generated by culturing the purified monocytes in Teflon bags for 7 days and adding rhuIFN to the cultured cells for the last 18 h. These MAK cells expressed differentiation-associated surface antigen MAX1, and were cytotoxic in vitro against tumour cell line U937. The MAK cells were infused at dose levels from 1 × 10⁷ to 5 × 10⁸ on an intrapatient dose-escalating schedule. No severe adverse side-effects occurred. Toxicity was mild to moderate [primarly fever (75%) and chills (32%)], non-dose-dependent, and non-cumulative. No consistent change in haemostatic function, or liver or renal function was observed. Dose-limiting toxicity was not reached at 5 × 10⁸ cells (optimal dose reproduced for each patient). The maximum tolerated dose was not determined. The immunomodulatory activity of i.v. infused MAK cells was demonstrated both in vivo by significant increases in granulocyte count and neopterin level in the patients' peripheral blood postinfusion and in vitro by secretory products (IL-1. TNF, neopterin, and thromboplastin-like substance) in the culture supernatants. The in vivo traffic patterns of autologous MAK cells labelled ex-vivo with¹¹¹In oxine were studied in 7 patients. Gamma imaging showed an immediate but transient lung uptake (<24 h), and a progressive uptake of radioactivity in the liver and spleen was seen from 6 h to 72 h post-infusion. Our results indicate that the preparation of high numbers of autologous, blood-derived MAK cells is a feasible procedure, and their transfusion is safe for patients. This immunotherapeutic approach seems to be encouraging from the point of view of establishing an adjuvant therapeutic modality in cancer patients with minimal residual disease.This work was supported in part by a grant 6911 from the Association pour la Recherche contre le Cancer (ARC), grants from the Ligue Nationale contre le cancer and the Ligues Regionales (Bas-Rhin, Haut-Rhin) contre le cancer, and contract 891013 from the Institut National pour la Santé et la Recherche Médicale (INSERM), France