Effect of oleuropein and sodium chloride on viability and metabolism of Lactobacillus plantarum

 The effect of the addition of oleuropein (OLP) and NaCl on the growth and the DL-lactic acid production of Lactobacillus plantarum DSM 10492 has been investigated by using an unconventional medium. The growth of L. plantarum was not inhibited by the addition of increasing amounts of untreated OLP in the presence or absence of glucose. However, bacterial cells grew in quantity slightly with OLP alone. The increased addition of NaCl was associated with a delay in growth. Moreover, there was no growth with 8% NaCl. The addition of both NaCl and OLP resulted in growth inhibition, and the survival of cells decreased strongly. The main fermentation product was DL-lactic acid, but acetic acid was also detected after a prolonged incubation. L. plantarum produced DL-lactic acid in the presence of OLP alone but its formation decreased with increasing levels of OLP. On the other hand, heat-treated OLP had a bactericidal effect. Received: 16 October 1995/Received last revision: 5 February 1996/Accepted: 12 February 1996     

Hyperforin inhibits vesicular uptake of monoamines by dissipating pH gradient across synaptic vesicle membrane

Extracts of Hypericum perforatum (St. John's wort) have antidepressant properties in depressed patients and exert antidepressant-like action in laboratory animals. The phloroglucinol derivative hyperforin has become a topic of interest, as this Hypericum component is a potent inhibitor of monoamines reuptake. The molecular mechanism by which hyperforin inhibits monoamines uptake is yet unclear. In the present study we try to clarify the mechanism by which hyperforin inhibits the synaptic vesicle transport of monoamines. The pH gradient across the synaptic vesicle membrane, induced by vacuolar type H(+)-ATPase, is the major driving force for vesicular monoamines uptake and storage. We suggest that hyperforin, like the protonophore FCCP, dissipates an existing Delta pH generated by an efflux of inwardly pumped protons. Proton transport was measured by acridine orange fluorescence quenching. Adding Mg-ATP to a medium containing 130 mM KCl and synaptic vesicles caused an immediate decrease in fluorescence of acridine orange and the addition of 1 microM FCCP abolished this effect. H(+)-ATPase dependent proton pumping was inhibited by hyperforin in a dose dependent manner (IC(50) = 1.9 x 10(-7) M). Hyperforin acted similarly to the protonophore FCCP, abolishing the ATP induced fluorescence quenching (IC(50) = 4.3 x 10(-7) M). Hyperforin and FCCP had similar potencies for inhibiting rat brain synaptosomal uptake of [3H]monoamines as well as vesicular monoamine uptake. The efflux of [3H]5HT from synaptic vesicles was sensitive to both drugs, thus 50% of preloaded [3H]5HT was released in the presence of 2.1 x 10(-7) M FCCP and 4 x 10(-7) M hyperforin. The effect of hyperforin on the pH gradient in synaptic vesicle membrane may explain its inhibitory effect on monoamines uptake, but could only partially explain its antidepressant properties.     

Sustainable management of fixed dunes: example of a pilot site in Brittany (France)

The sand-dunes of Quiberon was chosen as a pilot site to investigate experimentation in conservatory management. Sand burial is necessary to conserve the semi-fixed dune which is a transitory dynamic stage. In the fixed dune, low disturbances benefit the vegetation diversity while heavy ones create serious injury. An opening of the milieu can restore very fast but a naked substrate is difficult to heal. The deposition of gorse branches is then efficient to facilitate the restoration. The fixed dune biodiversity is linked to human activities. Disturbances, natural or not, may be used as management tools.     

Effect of phenolic compounds on the co-metabolism of citric acid and sugars by Oenococcus oeni from wine

AIMS: The goal of this study was to examine the growth of Oenococcus oeni in the presence of phenolic compounds under wine conditions and to see how these compounds affect bacterial metabolism. METHODS AND RESULTS: Phenolic compounds have been added to a basal medium that simulates the composition of wine. Fifty milligrams per litre or more of phenolic compounds stimulated bacterial growth. Oenococcus oeni seemed to use citric acid and trehalose, if they were present, before glucose and fructose. Citrate was completely exhausted in three days and the yield of acetate was higher when phenolic compounds were present. CONCLUSIONS: Phenolic compounds reduced the rate of sugar consumption and enhanced citric acid consumption, increasing the yield of acetic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: This study allows a better knowledge of co-metabolism of citric acid and sugars by O. oeni in the presence of phenolic compounds of wine.     

Contraceptive Use and Pregnancy Outcomes among Opioid Drug-Using Women: A Retrospective Cohort Study

Objective

The contraceptive needs of illicit opioid users differ from non-drug users but are poorly understood. The aim of this study was to describe contraceptive use and pregnancy outcomes in opioid-using women, and to examine their association with a range of risk factors.

Method

This retrospective cohort study used UK general practice records, Treatment Outcomes Profile and National Drug Treatment Monitoring System data, and a nested data validation exercise. A cohort of 376 women aged 20–61 years were in active treatment for opioid addiction in October 2010 at two specialised primary care practices in North-East England. Outcomes were age-adjusted prevalence estimates for contraceptive use and pregnancy outcomes in users of illicit opioids. The association between lifestyle-related risk factors and contraception was explored.

Results

Drug-using women made lower use of planned (non-condom) contraception (24% vs 50%, p<0.001), had more frequent pregnancy terminations (0.46 vs. 0.025, p = 0.004) and higher annual incidence of chlamydia (1.1% vs. 0.33%, p<0.001), when compared with age-matched population data. Specifically, there was low use of oral contraceptives (4% vs. 25%, p<0.001), IUCD (1% vs. 6%, p<0.001), and sterilisation (7% vs. 6%, p = 0.053), but higher rates of injectable contraceptives (6% vs. 3%, p = 0.003). A total of 64% of children aged <16 years born to this group did not live with their mother. No individual risk factor (such as sex-working) significantly explained the lower use or type of non-condom contraception.

Conclusions

This is the first study to describe planned contraceptive use among drug-users, as well as the association with a range of risk factors and pregnancy outcomes. The low uptake of planned contraception, set against high rates of terminations and sexually transmitted disease demonstrates the urgent clinical need to improve contraceptive services, informed by qualitative work to explore the values and beliefs influencing low contraceptive uptake.     

The identification of a series of novel, soluble non-peptidic neuropeptide Y Y2 receptor antagonists

The identification and subsequent optimisation of a selective non-peptidic NPY Y2 antagonist series is described. This led to the development of amine 2, a selective, soluble NPY Y2 receptor antagonist with enhanced CNS exposure.     

Enhancing yeast cell viability after dehydration by modification of the lipid profile

In the present study, we analysed metabolite features during the dehydration-rehydration process for different yeast species genetically closely related to S. cerevisiae, in order to determine whether metabolites might play a role in cell viability. We ranked the species S. cerevisiae, S. paradoxus, S. kudriavzevii, L. kluyveri, N. castellii, S. mikatae, S. bayanus, and S. servazzii according to their viability rate after the dehydration-rehydration process, and showed that desiccation tolerance across the species did not correlate with the intracellular content of trehalose or glycogen. Cell lipid composition was also investigated during this process, to see whether the content of triacylglycerols and phosphatidylcholine showed significant variations across the species. The increase of phosphatidylcholine level increase in both S. paradoxus and S. bayanus cells grown in supplemented media enhanced both their cell viability after stress imposition and lipid storage.