Role of botrytized grape micro-organisms in SO2 binding phenomena.

AIMS: The purpose of this work was to study the involvement of micro-organisms, which develop together with Botrytis cinerea on grapes, in the SO2 binding power of musts. METHODS AND RESULTS: Yeasts and bacteria were involved. Most bacteria were acetic acid bacteria, mainly of the Gluconobacter genus. Unlike oxidative yeasts, Gluconobacter produce gluconic acid (in balance with delta-gluconolactone) from glucose, 5-oxofructose from fructose and dihydroxyacetone from glycerol. Production of carbonyl compounds from other sugars and polyols was not detected or was very weak. CONCLUSION: Acetic acid bacteria are responsible for the increases in SO2 binding power of musts from botrytized grapes by oxidizing the three main sugars of these grapes. SIGNIFICANCE AND IMPACT OF THE STUDY: Up to 80% of the SO2 binds with products of Gluconobacter which easily grow on 'botrytized' grapes. Depending on climatic conditions, some vintages are particularly difficult to stabilize.

Role of carbonyl compounds in SO(2) binding phenomena in musts and wines from botrytized grapes.

Carbonyl compounds play an important role in musts from botrytized grapes. Some of them, such as glyoxal and methylglyoxal, may explain a considerable part of bindable SO(2). Others, such as 2- and 5-oxogluconic acids, produced by gluconic acid oxidation in proportions respectively from 2.5 per 1 play an interesting role as SO(2) binding indicator. Finally, the levels of some compounds such as dihydroxyacetone, 5-oxofructose, and delta-gluconolactone in balance with gluconic acid are well correlated with SO(2) binding powers and also explain a large part of the bindable SO(2) in musts. During alcoholic fermentation, only dihydroxyacetone among these three compounds is metabolized by yeast. Thus, two compounds present in grapes, delta-gluconolactone and 5-oxofructose, with three yeast SO(2)-binding byproducts, ethanal, pyruvic, and 2-oxoglutaric acids, explain much of the SO(2) binding power in wines from botrytized grapes.

PBF-2 is a novel single-stranded DNA binding factor implicated in PR-10a gene activation in potato.

Elicitor-induced activation of the potato pathogenesis-related gene PR-10a requires a 30-bp promoter sequence termed the ERE (elicitor response element) that is bound by the nuclear factor PBF-2 (PR-10a binding factor 2). In this study, PBF-2 has been purified to near homogeneity from elicited tubers through a combination of anion-exchange and DNA affinity chromatography. Evidence demonstrates that inactive PBF-2 is stored in the nuclei of fresh tubers and becomes available for binding to the ERE upon elicitation. A protein with an apparent molecular mass of 24 kD (p24) is a DNA binding component of PBF-2. A cDNA encoding p24 has been cloned and encodes a novel protein with a potential transcriptional activation domain that could also act as a single-stranded DNA binding domain. Both PBF-2 and the cDNA-encoded protein bind with high affinity to the single-stranded form of the ERE in a sequence-specific manner. The inverted repeat sequence of the ERE, TGACAnnnnTGTCA, is critical for binding of this factor in vitro and for PR-10a expression in vivo, supporting the role of PBF-2 as a transcriptional regulator.

Isolation, properties and behaviour of tyramine-producing lactic acid bacteria from wine.

Wines containing high levels of biogenic amines were investigated for the presence of tyramine-producing strains. Two different Lactobacillus brevis (IOEB 9809 and IOEB 9901) able to produce the amine were isolated. None of the isolated strains identified as Oenococcus oeni formed tyramine. In addition, other Lact. brevis and Lact. hilgardii strains from our collection (IOEB) and the American Type Culture Collection (ATCC) were strong tyramine producers. Lactobacillus brevis IOEB 9809 and Lact. hilgardii IOEB 9649 were found to produce tyramine and phenylethylamine simultaneously. The conditions that can influence tyramine formation in wine were evaluated for three strains of Lact. brevis (IOEB 9809 and IOEB 9901) and Lact. hilgardii (IOEB 9649). Tyrosine was the major factor affecting tyramine formation and was enhanced by the presence of sugars, mainly glucose. Tyrosine decarboxylase (TDC) activity greatly depended on the presence of the precursor, which suggested that tyrosine induced the TDC system. These results indicate that Lactobacillus could be the lactic acid bacteria responsible for tyramine production in wine.

Use of ipsilateral greater saphenous vein as a valved transplant in management of post-thrombotic deep venous insufficiency: long-term results.

Incompetence of the deep venous valve is a common feature of post-thrombotic deep venous insufficiency. Various surgical techniques have been proposed to treat reflux. In this study we describe long-term results of a novel transposition technique using the ipsilateral greater saphenous vein. From 1984 to 1994 we used this procedure to treat 16 patients including 10 men and 6 women with a mean age of 56 years (range: 25 to 76 years). In all 16 cases the indication for surgery was incapacitating pain associated with recurring ulceration in 9 patients. From the results of using this technique we conclude that transposition using the ipsilateral greater saphenous vein is safe and effective with good mid-term results, especially for pain. For ulcers the primary success rate was 55% but this increased to 84% with proper surveillance and treatment of secondary insufficiency of the superficial venous system.

Hydroxylated polychlorinated biphenyls (PCBs) as estrogens and antiestrogens: structure-activity relationships.

The effects of structure on the estrogenicity and antiestrogenicity of hydroxylated polychlorinated biphenyls were investigated using the following estrogen-sensitive assays: competitive binding to the rat and mouse cytosolic estrogen receptor (ER); immature rat and mouse uterine wet weight, peroxidase and progesterone receptor (PR) levels; induction of luciferase activity in HeLa cells stably transfected with a Gal4:human ER chimera and a 17mer-regulated luciferase reporter gene; proliferation of MCF-7 human breast cancer cells; induction of chloramphenicol acetyl transferase (CAT) activity in MCF-7 cells transiently transfected with a full-length human ER expression plasmid and a plasmid containing an estrogen-responsive vitellogenin A2 promoter linked to a CAT reporter gene. The chemicals synthesized for this study contained a 4-hydroxy group in one ring, a 2- or 3-chloro substituent meta or ortho to the hydroxyl group, and variable substitution (2',3',4',5'-, 2',3',4',6'-, 2',3',5',6'-tetrachloro and 2',4',6'-trichloro) in the chlorophenyl ring. The compounds included: 2,2',3',4',5'- (A), 2,2',3',4',6'- (B), and 2,2',3',5',6'-pentachloro- (C); 2,2',4',6'-tetrachloro-4-biphenylol (D); 2',3,3',4',5'- (E), 2',3,3',4',6'- (F), and 2',3,3',5',6'-pentachloro (G); and 2',3,4',6'-tetrachloro-4-biphenylol (H). With the exception of 2',3,4',6'-tetrachloro-4-biphenylol (H), all of the compounds competitively bound to the mouse and rat ER with relative binding affinities [compared to 17beta-estradiol (E2)] varying from 1.4 x 10(-3) to 5.3 x 10(-5). The structure-ER binding relationships for the hydroxy-PCB congeners were different in the rat and mouse, and no dose-dependent estrogenic activities were observed in the mouse or rat uterus. Several hydroxy-PCB congeners exhibited antiestrogenic activity (primarily in the mouse uterus) and two compounds, 2,2',3',5',6- and 2,2',3',4',6'-pentachloro-4-biphenylol, inhibited E2-induced uterine wet weight, PR binding, and peroxidase activity in the mouse uterus. 2,2',3',4',5'- and 2,2',3',4',6'-Pentachloro-4-biphenylol induced CAT activity in MCF-7 cells transiently transfected with the Vit-CAT plasmid; the remaining congeners did not induce CAT activity but exhibited antiestrogenic activity in MCF-7 cells cotreated with 10(-9) E2 plus 10(-5) M hydroxy-PCBs. Complementary structure-estrogenicity relationships were observed utilizing the HeLa cell luciferase induction and MCF-7 cell proliferation assays. The placement of the 2- or 3-chloro groups in the phenolic ring had minimal effects on estrogenic activity, whereas 2,4,6-trichloro- and 2,3,4,6-tetrachloro substitution in the chlorophenyl ring (B, D, F, and H) were required for this response. Substitution in the phenolic ring was also not important for structure-antiestrogenicity relationships, and the most active compounds (A, C, E, and G) contained 2',3',4',5'- and 2',3',5',6'-tetrachlorophenyl groups. Thus, structure-estrogenicity/antiestrogenicity relationships for this series of hydroxy-PCBs were complex and response-specific.

RIP 140 enhances nuclear receptor-dependent transcription in vivo in yeast.

RIP140 has previously been cloned as a factor that interacts with the estrogen receptor (ER) in vitro. We demonstrate in this study that RIP140 is a co-factor for nuclear receptor in yeast. RIP140 enhances the ER transcriptional activity by increasing 1.5- to 4-fold the induction factor of the reporter gene response at saturating hormone concentrations, this effect being magnified at suboptimal doses of estradiol. Moreover, RIP140 decreases the ED50 of the dose-response curve. These effects are recovered with an N-terminal truncated ER, but impaired by point mutations that abolish AF2-AD activity. We did not observe any modulation of the partial agonist 4-hydroxytamoxifen activity in the presence of RIP140. Thus, RIP140 modulates transcriptional activity of ER through the AF2-AD domain and in a agonist-dependent fashion. RIP140 is also a strong coactivator for the retinoid pathway, as its expression enhances 10-fold the transactivation of a chimeric retinoic acid-alpha receptor at saturant hormone concentration and left shifted 5-fold the ED50 of the dose-response curve. We have investigated whether RIP140 could be involved in cross-talk between estrogenic and retinoid pathways.

Antiestrogenic activity of hydroxylated polychlorinated biphenyl congeners identified in human serum.

Several hydroxylated polychlorinated biphenyls (PCBs) identified in human serum have been synthesized and these include 2,2',3,4',5,5'-hexachloro-4-biphenylol; 2,3,3',4',5-pentachloro-4-biphenylol; 2',3,3',4',5-pentachloro-4-biphenylol; 2,2',3,3',4',5-hexachloro-4-biphenylol; 2,2',3,3',4',5,5'-heptachloro-4-biphenylol; 2,2',3,4',5,5',6-heptachloro-4-biphenylol; and 2,2',3',4,4',5,5'-heptachloro-3-biphenylol. The hydroxy-PCBs exhibited minimal binding to the rat uterine cytosolic estrogen receptor (ER) and did not induce proliferation of estrogen-responsive MCF-7 human breast cancer cells at concentrations ranging from 10(-5) to 10(-8) M. The estrogenic activity of these compounds was further investigated utilizing two estrogen-responsive in vitro bioassays, namely, (i) HeLa cells stably transfected with a Gal4:human ER chimera and a 17-mer-regulated luciferase reporter gene, and (ii) MCF-7 cells transiently transfected with a full-length human ER expression plasmid and a plasmid containing an estrogen-responsive vitellogenin A2 promoter linked to a chloramphenicol acetyl transferase (CAT) reporter gene. None of the hydroxy-PCBs significantly induced luciferase activity in the stably transfected HeLa cells or CAT activity in MCF-7 cells at concentrations as high as 10(-5) M. The antiestrogenic effects of the hydroxy-PCBs were also investigated using the same bioassays in which the cells were cotreated with 17beta-estradiol plus the hydroxy-PCBs. All of the hydroxy-PCB congeners inhibited one or more estrogenic response, and one congener, 2,2',3,4',5,5',6-heptachloro-4-biphenylol, inhibited 17beta-estradiol-induced cell proliferation and CAT activity in MCF-7 cells and luciferase activity in HeLa cells.

In vitro and in vivo interactions between nuclear receptors at estrogen response elements.

To study mechanisms involved in the antiestrogenic effect of retinoic acid (RA), previously described in mammalian cells, we used in vitro and in vivo approaches. One hypothesis was direct competition between nuclear receptors (ER, RAR and RXR) at the DNA level. We first showed in vitro that the RAR/RXR heterodimer could weakly bind an ERE and that retinoid receptors reduced binding of ER to an ERE. We next checked whether, in yeast, direct competition between receptors that recognize the same responsive element could be monitored in a reconstituted heterologous estrogen-responsive system, by determining the expression of a reporter gene. We then co-transformed RAR and RXR in an estrogenic responsive strain. This model demonstrated that, even though RAR/RXR was able to bind an ERE, the addition of retinoic acid had no inhibitory effect on estrogen-induced responses in this yeast system, unlike in mammalian cells. Interference between these receptors should require other factors than interactions at the ERE level. This model could be used to identify mammalian factors interacting with estrogen and retinoic acid receptors which could play a role in crosstalk between these receptors.

Endovascular repair of iliac artery aneurysm with Endoprosystem I: a multicentric French study.

Due to their position deep in the pelvis, the classical surgical treatment of iliac artery aneurysm leads to a high morbidity and mortality rate. The transfemoral percutaneous repair of these aneurysms is now possible thanks to a new device the endoprosystem I from "Mintech". We began in 1994 a study including radiological, cardiac and vascular centers all of them skilled in endovascular procedures. 27 patients entered the study: 1 patient died, 2 attempt failed and 2 presented leakage: the immediate failure rate was then 18.5%. For the late result (min 6, Max 19, mean 12 months) we had 1 thrombosis treated by surgery, 1 restenosis treated by PTA. We did not see any polyester dilatation or reactivation of aneurysm at the scan control at one year. We conclude that the percutaneous treatment of iliac aneurysm is possible and safe but we need long term result to validate the method.

Assessing the estrogenic and dioxin-like activities of chemicals and complex mixtures using in vitro recombinant receptor-reporter gene assays.

In vitro recombinant receptor-reporter gene assays have been used to assess and rank the potency of chemicals and complex mixtures suspected of possessing estrogen and (or) aryl hydrocarbon receptor (AhR) mediated activity. The environmental estrogen (E2) bioassay consists of a Gal4-human estrogen receptor chimeric construct (Gal4-HEGO) and a Gal4-regulated luciferase reporter gene (17m5-G-Luc) that have been stably integrated into HeLa cells. The assay exhibits 10-fold induction in luciferase reporter gene activity following treatment with 1 nM 17 beta-estradiol and has a detection limit of approximately 5 pg of 17 beta-estradiol/mL. The AhR bioassay uses Hepa 1c1c7 wild-type cells transiently transfected with a dioxin response element regulated luciferase reporter gene. These assays were used to assess the estrogen and dioxin-like activities of naringenin, atrazine, and simazine and complex mixtures such as pulp and paper mill black liquor and urban air particulates. The activities of these chemicals and complex mixtures are confirmed using the pure antiestrogen ICI 164,384 and in in vitro gel retardation assays. Results of this study demonstrate the utility of in vitro recombinant receptor-reporter gene assays in identifying and assessing the estrogenic and dioxin-like activities of chemicals and complex mixtures.

[Applications of luminescence reactions in life science]. / Applications des réactions de luminescence dans le domaine des sciences de la vie.

Bioluminescence and chemiluminescence have emerged in the last decade as a major tool for biochemical and biological studies. Several very sensitive assays have been developed in our laboratory such as enzymatic assays, immunoassays and detection of nucleic acids. The use of a new instrumentation allowing to dimensional photon counting has permit the emergence of new investigations at the cellular level. In addition to the advantages of sensitivity and the real-time non-invasive nature of this detection system, the imaging potential of using low-light and photon counting video cameras has been particularly influential in establishing its ascendence over more traditional systems. This review provides a reflection in this field through several applications in life sciences.

Transluminal recanalization of occluded iliac arteries: a surgical experience.

The purpose of this study was to evaluate the feasibility of transluminal techniques in an unselected group of patients and to assess long-term outcome in successful procedures. All patients in whom iliac artery recanalization was attempted were included in this study. Patients with an occluded prosthesis or recent embolism were excluded. A total of 37 patients were studied. Assessment of the success or failure of the procedure was based on the results of control arteriography. Recanalization was deemed successful in 31 patients. This study demonstrates that transluminal recanalization of occluded iliac arteries by a surgeon is indeed feasible. Primary patency was 66% at 24 months. The potential risk, however, is long-term restenosis. Thus follow-up examination every 6 months is recommended including pressure index measurements after exercise and color Doppler ultrasonography of the recanalized zone.

Histamine production by wine lactic acid bacteria: isolation of a histamine-producing strain of Leuconostoc oenos.

Populations of Leuconostoc oenos were harvested from wines containing a relatively high concentration of biogenic amines. Cultivation of the biomass in synthetic media and wine showed that it consisted of histamine-producing strains. Histamine levels after culture depended on the quantity of precursor available and on the presence of yeast lees, which certainly enriched the medium in histidine. Ethanol and pH, which control bacterial growth rate and total population, were also significant factors: pH and low ethanol concentration enhanced histamine production. Strain Leuc. oenos 9204 was isolated and studied since it retained its ability to produce histamine after several transfers. In synthetic medium this strain produced large amounts of histamine especially in the poorest nutritional conditions (no glucose, no L-malic acid). These results clearly demonstrate that Leuc. oenos involved in wine-making might play a role in biogenic amine production. The vinification method might also influence the final amine concentration in wine.

[Therapeutic strategy for large cervical, mediastinal metastatic mature teratomas and large retro- and intraperitoneal lesions]. / Stratégie thérapeutique devant de volumineuses métastases tératomateuses matures cervicales, médiastinales et d'énormes lésions rétro et intra-péritonéales.

A 27 years old man was treated after surgery and classic chemotherapy for a right testicular teratoma (stage IV). Two months after the end of chemotherapy the patient developed "a Growing Teratoma Syndrome" with left subclavian and mediastinal nodes enlargement and bulky abdominal cystic masses with vena cava compression, collateral circulation and oedema of inferior members. Four debulking surgical approaches: cervical, thoracic and abdominal were performed and permitted complete functional recovery.