Valproate release from polycaprolactone implants prepared by 3D-bioplotting

In this study we examined the release kinetics of valproate from polycaprolactone (PCL) implants constructed for local antiepileptic therapy. The PCL implants were produced with a novel 3D-Bioplotting technology. Release kinetics were determined by superfusion of these implants. Valproate was measured in the superfusate fractions with high pressure liquid chromatography (HPLC). The HPLC measurements were linear over a concentration range of 10-500 microg/mL for valproate and the limit of quantification was found to be 9 microg/mL. The HPLC method used is simple, accurate and sensitive. Within the first day, valproate (10% w/w)-PCL implants released already 77% of the maximum possible liberated amount whereas (5% w/w)-PCL implants released only 53%. After four days, 88% of valproate was released from (10% w/w)-PCL implants and 94% valproate from (5% w/w)-PCL implants. When valproate was ground before the 3D-Bioplotting process, only 63% from (10% w/w)-PCL implants was released within the first day. This released amount of ground valproate was significantly lower compared to that which was not ground from the (10% w/w)-PCL implants. After three days of superfusion a total amount of 89% of ground valproate within the implants was released, corresponding to 88% of non-ground valproate after four days. The fast releasing PCL implants can be used to study acute effects of locally applied valproate on epileptogenesis in vivo after initiation of an epileptic focus in an animal model. The corresponding biocompatibility may also be analysed.

Diurnal pattern of cortisol and amylase output in postnatal depression

Objective

This study investigated the diurnal output of saliva cortisol and saliva amylase in women with symptoms of depression postnatally.

Method

Twenty one depressed and 30 non depressed women at 7.5 weeks postpartum, and 21 non perinatal controls, collected saliva at waking, 30 minutes, and three and twelve hours post waking.

Results

Women who were not depressed postnatally showed a pattern of cortisol secretion over the day similar to non perinatal controls. There was a significant difference in diurnal pattern between postnatally depressed and postnatally non depressed women, due to a difference in the first two time points (waking and +30 mins): compared to the other two groups who each had a significant increase in cortisol levels from waking to +30 minutes, the depressed women had significantly higher cortisol levels at waking and no increase at +30 minutes. Analyses of amylase are underway and will be presented.

Conclusion

The lack of a morning rise in the depressed women is similar to that reported for Post-traumatic Stress Disorder and chronic fatigue syndrome and may reflect a response, in vulnerable women, to the marked cortisol withdrawal that occurs after delivery. Alternatively it could be a trait marker for women at risk of developing postnatal depression.

Salivary alpha-amylase stability, diurnal profile and lack of response to the cold hand test in young women

Salivary cortisol measurement has proved useful for the non-invasive study of the hypothalamic-pituitary-adrenocortical axis, and salivary alpha-amylase has been suggested as a comparable marker for the sympathetic system. Despite some studies showing an increase in salivary alpha-amylase after challenges that stimulate the sympathetic nervous system, questions remain about interpretation. The aims of this study were to explore the stability of salivary alpha-amylase, its diurnal profile, response to the cold hand test, and correlation with cortisol. Salivary alpha-amylase was stable following 5 days at room temperature, and five freeze-thaw cycles. Its diurnal profile was opposite to that of cortisol. There was no salivary alpha-amylase response to the cold hand stress test, in the morning (11am) or afternoon (3pm), unlike cortisol which showed a response in the afternoon in the same samples. There was no correlation between salivary alpha-amylase and cortisol at any time. In conclusion, salivary alpha-amylase is stable to a range of conditions. Its diurnal pattern is compatible with sympathetic stimulation. Lack of response to the cold hand test suggests that secretion of salivary alpha-amylase is controlled by mechanisms more complex than sympathetic regulation alone.

Nitrate and nitrite concentrations in rabbit saliva Comparison with rat saliva

The purpose of this work was to investigate the interest of rabbits for studying pharmacology and toxicology of dietary nitrate. Twenty-one females were given 1, 300 and 600mg/l nitrate in drinking water for 11 weeks. Saliva and blood were analysed for nitrate/nitrite. There is a linear relationship between the amounts of nitrate ingested and amount of nitrate in saliva, contrary to what is observed in rats. However, salivary nitrite concentrations remain low, and nitrate reductase activity in the oral cavity of the rabbit seems very weak.

The HPA axis and perinatal depression: a hypothesis

Episodes of depression and anxiety are as common during pregnancy as postpartum. Some start in pregnancy and resolve postpartum, others are triggered by parturition and some are maintained throughout. In order to determine any biological basis it is important to delineate these different subtypes. During pregnancy, as well as the rise in plasma oestrogen and progesterone there is a very large increase in plasma corticotropin releasing hormone (CRH), and an increase in cortisol. The latter reaches levels found in Cushing's syndrome and major melancholic depression. Levels of all these hormones drop rapidly on parturition.We here suggest that the symptoms of antenatal and postnatal depression may be different, and linked in part with differences in the function of the hypothalamic pituitary adrenal (HPA) axis. There are two subtypes of major depression, melancholic and atypical, with some differences in symptom profile, and these subtypes are associated with opposite changes in the HPA axis. Antenatal depression may be more melancholic and associated with the raised cortisol of pregnancy, whereas postnatal depression may be more atypical, triggered by cortisol withdrawal and associated with reduced cortisol levels. There is evidence that after delivery some women experience mild bipolar II depression, and others experience post traumatic stress disorder. Both of these are associated with atypical depression. It may also be that some women are genetically predisposed to depression of the melancholic type and some to depression of the atypical type. These women may be more or less vulnerable to depression at the different stages of the perinatal period.

Liver and kidney concentrations of vanadium in oiled seabirds after the Erika wreck

Vanadium was measured by atomic absorption spectrophotometry in the liver and kidney of several oiled seabirds that were stranded on the French Atlantic coasts after the Erika wreck and died in wildlife care Centers. Estimated averages were 30 to 77 ng g(-1) wet weight (ww) in the liver and 52 to 72 ng g(-1) wet weight in the kidney. These concentrations were not higher in oiled birds than in dead birds found later, without visible traces of petroleum on beaches not affected by the Erika pollution. Vanadium hepatic and renal concentrations do not seem to be appropriate biomarkers for recent exposure to fuel in seabirds.

Ethanol toxicosis from the ingestion of rotten apples by a dog

We report a case of ethanol intoxication from massive rotten apples ingestion. The dog exhibited vomiting, ataxia, tremors, dehydratation, and died 48 h later with an alcoholemia of 300 mg/dL.

GCMB, a second human homolog of the fly glide/gcm gene

Glial cells play fundamental roles in neurogenesis. In addition, defective or abnormal gliogenesis is associated with severe diseases. To understand the molecular basis of such diseases, it is crucial to identify the genes promoting normal gliogenesis. Here we identify GCMB, which encodes a human protein homologous to the fly glial promoting factor glial cell deficient/glial cell missing (glide/gcm).

[Zurich Intervention Planning and Evaluation Form (ZIPEF): a procedure for quality control of therapeutic interventions]

This paper introduces the Zurich Intervention Planning and Evaluation Form (ZIPEF). The instrument covers (1) treatment problems, (2) interventions as to type, duration, and time expenditure, (3) treatment outcome and (4) causal factors. A total of 413 treatment problems were evaluated with the ZIPEF in a public child and adolescent psychiatric service. Depending on the target (e.g. symptoms, personality, relationship) the distribution of types of intervention differed. Time expenditures were significantly higher only for client-centred interventions than for parent counseling and similar for all other interventions. Treatment outcome and cooperation were independent from type of intervention. The main causal factor of treatment outcome for almost all types of interventions was cooperation followed by resources in some types of intervention. Complexity of the treatment problem tended to be another important determinant for treatment outcome. In summary, the ZIPEF can contribute to quality management in the area of intervention planning and evaluation of clienteles with mental health problems.

Gliogenesis depends on glide/gcm through asymmetric division of neuroglioblasts

Some neurons and glial cells originate from neuroblasts and glioblasts, stem cells that delaminate from the ectoderm of developing fly embryos. A second class of glial cells and neurons differentiates from multipotent precursors, the neuroglioblasts. The differentiation of both glial cell types depends on glial cell deficient/glial cell missing (glide/gcm). Although it has been shown that this transcription factor promotes gliogenesis at the expense of neurogenesis, the cellular mechanisms underlying this fate choice are poorly understood. Using loss and gain of function glide/gcm mutations here we show that the cell fate choice takes place in the neuroglioblast, which divides and produces a glioblast and a neuroblast. Such choice requires the asymmetric distribution of glide/gcm RNA, which accumulates preferentially on one side of the neuroglioblast and is inherited by one cell, the presumptive glioblast. Interestingly, glial cells can differentiate from cells that delaminate as neuroglioblasts or they can arise from cells that start expressing glide/gcm several hours after delamination of a neuroblast. Altogether, these findings identify a novel type of asymmetric cell division and disclose the lineage relationships between glia and neurons. They also reveal the mode of action of the glide/gcm promoting factor.

Residues depletion in egg after warfarin ingestion by laying hens

Accidental ingestion of anticoagulant rodenticide bait by poultry rarely leads to clinical signs of poisoning, but represents a risk for the consumer because of potential residues in the laid eggs. An assay was conducted for a better risk assessment. Three groups of laying hens were given a single oral dose of 10, 30 or 90 mg warfarin/kg BW. Eggs were collected for 14 d, and warfarin was analyzed by reversed-phase high-performance liquid chromatography. Warfarin was present in the white for 3 to 4 d following anticoagulant ingestion, while concentration increased in the yolk until the 5th or 6th d, and then gradually decreased. At the end of experimentation, warfarin was still detected at below 100 ng/g in the yolk of eggs in each group.

Effect of added drinking water nitrate on the vitamin A status of rabbits

In animals, chronic exposure to nitrates has been shown to affect vitamin A nutrition, and researchers have explored this effect with conflicting results. To study this relationship, 24 female rabbits were given 8, 250 or 500 mg nitrate/L drinking water for 22 w, and their second litters were given the same dose for 5 w from 18 to 53 d of age. Liver samples were analyzed for retinol and retinyl palmitate. There was no effect of the nitrate on total liver vitamin A stores, but the balance between esterified and nonesterified forms of retinol was altered in pregnant females and their weaned young.

[Influence of nitrates on reproduction in domestic mammals]

Nitrates and nitrites ingestion has been linked to adverse effects on reproductive efficiency, on the one hand by abortion in acute or subacute toxicity, on the other hand by impairment of fertility in chronic exposition. However, experimental studies show heterogeneous results and proposed mechanisms are still hypothetic. Experimental studies realised in rabbit in National Veterinary School of Nantes are presented. No detrimental effect on reproduction performances was seen in female rabbits given nitrate in the drinking water at levels of 250 or 500 mg/l during 22 weeks, but a decrease in retinol concentration in the liver of young rabbits born of exposed mother, and drinking themselves water with nitrate during 5 weeks, was observed.