[Bacterial colonization and home mechanical ventilation: prevalence and risk factors]

OBJECTIVE

To investigate the prevalence of bacterial contamination of ventilators and colonization of patients, the bacteria implicated, and predisposing factors in noninvasive home ventilation.

MATERIAL AND METHODS

Forty patients on a home noninvasive ventilation program (mean [SD] age: 63.1 [12] years; time on ventilation: 30.7 [25] months; daily use: 8.1 [2] hours) were enrolled in this descriptive cross-sectional study. Microbiological samples for semiquantitative cultures were swabbed from the ventilator (mask and tubing) and the nostrils. A questionnaire was completed on the underlying disease, time on the ventilation program, type of ventilator, presence of a humidifier, and attention to ventilator cleanliness and maintenance. We defined "colonization" as the presence of microorganisms in the nostrils without evidence of a host immune response, and "contamination" as the presence of surface microorganisms (on tubing or the nasal mask).

RESULTS

Potentially pathogenic bacteria were isolated from 6 ventilators (15%) and the nasal swabs of 10 patients (25%). Staphylococcus aureus was the most frequently isolated one (in 5 ventilators and 6 patients--contamination coinciding with colonization in 3 cases). Other potentially pathogenic bacteria isolated were Proteus species (from the nostrils of 2 patients) and an unidentified gram-negative bacillus from the ventilator. On analysis by underlying disease, 60% of the patients with obesity had been colonized. No other findings of note were obtained for other diseases. Contamination and colonization correlated with attention to cleanliness and maintenance of the ventilator but not with type of ventilator, time on the ventilation program, or use of a humidifier.

CONCLUSIONS

Home mechanical ventilators are a potential source of nasal colonization. The most frequently encountered microorganism was S. aureus. The degree of ventilator cleaning and disinfection seems to affect contamination; thus it is necessary to impress on patients the need for adequate maintenance of their ventilators.

Escitalopram versus citalopram: the surprising role of the R-enantiomer

RATIONALE

Citalopram is a racemate consisting of a 1:1 mixture of the R(-)- and S(+)-enantiomers. Non-clinical studies show that the serotonin reuptake inhibitory activity of citalopram is attributable to the S-enantiomer, escitalopram. A series of recent non-clinical and clinical studies comparing escitalopram and citalopram to placebo found that equivalent doses of these two drugs, i.e. containing the same amount of the S-enantiomer, showed better effect for escitalopram. These results suggested that the R-citalopram in citalopram inhibits the effect of the S-enantiomer.

OBJECTIVE

To review the pharmacological and non-clinical literature that describes the inhibition of escitalopram by R-citalopram, as well as the implications of this inhibition for the clinical efficacy of escitalopram compared to citalopram.

METHODS

The information in this review was gathered from published articles and abstracts.

RESULTS

In appropriate neurochemical, functional, and behavioural non-clinical experiments, escitalopram shows greater efficacy and faster onset of action than comparable doses of citalopram. The lower efficacy of citalopram in these studies is apparently due to the inhibition of the effect of the S-enantiomer by the R-enantiomer, possibly via an allosteric interaction with the serotonin transporter. Data from randomised clinical trials consistently show better efficacy with escitalopram than with citalopram, including higher rates of response and remission, and faster time to symptom relief.

CONCLUSION

The R-enantiomer present in citalopram counteracts the activity of the S-enantiomer, thereby providing a possible basis for the pharmacological and clinical differences observed between citalopram and escitalopram.

Vaginal misoprostol 800 μg every 12 h for second-trimester abortion

The objective of the study was to evaluate the efficacy and safety of 800 microg misoprostol every 12 h, up to three doses, for pharmacological second-trimester abortion. The misoprostol doses were always administered by doctors into the vagina. Two-hundred and sixty-nine women with gestations within 12 and 20 weeks were recruited into the study. The main outcomes measured were successful abortion (passage of fetus and placenta without surgery), side effects and mean drop in hemoglobin, vaginal bleeding and mean time of return of menstruation. Complete abortion occurred in 245/269 (91.1%, 95% confidence interval 87-94%) patients. Vaginal bleeding lasted 15.7 +/- 4.1 days. The mean drop in hemoglobin, calculated 24 h after abortion, were statistically significant (p = 0.0001), as also was the mean hemoglobin measured 14 days after abortion, but without clinical relevance. According to the results obtained, 800 microg of misoprostol administered every 12 h, up to a maximum of three doses, could be a valid method for abortion within 12 and 20 weeks of gestation.

Influence of the substrate on the ultrastructure of Pleurotus pulmonarius fruit body primordia

Pleurotus pulmonarius fruit body primordia (FBP) formed on potato extract agar (PEA) and wheat straw-based media (WS) were studied. When grown on PEA, FBP hyphae had a large number of vacuoles and less stainable cytoplasmic material. In contrast, when grown on WS, there was abundant cytoplasmic material and fewer vacuoles. FBP grown on WS had a more well-defined mushroom shape than those grown on PEA. The average hyphal diameters on PEA and WS were 4.15 and 3.52 micro m, respectively; the average hyphal lengths were 11.75 and 11.80 micro m, respectively. The control mechanisms regulating formation of the normal shape and size of FBP might be more dependent on the amount of cytoplasmic material than on the physical volume of the hyphal compartment. Since the ultrastructure of the hyphal compartment, which makes up the substance of the FBP, depends on the substrate in which the FBP has been grown, the composition of the substrate may be important for manipulating the nutritive and organoleptic characteristics of the mushroom crop.

Modern aspects of mushroom culture technology

The production and culture of new species of mushrooms is increasing. The breeding of new strains has significantly improved, allowing the use of strains with high yield and resistance to diseases, increasing productivity and diminishing the use of chemicals for pest control. The improvement and development of modern technologies, such as computerized control, automated mushroom harvesting, preparation of compost, production of mushrooms in a non-composted substrate, and new methods of substrate sterilization and spawn preparation, will increase the productivity of mushroom culture. All these aspects are crucial for the production of mushrooms with better flavor, appearance, texture, nutritional qualities, and medicinal properties at low cost. Mushroom culture is a biotechnological process that recycles ligninocellulosic wastes, since mushrooms are food for human consumption and the spent substrate can be used in different ways.

Simple staining detects ultrastructural and biochemical differentiation of vegetative hyphae and fruit body initials in colonies of Pleurotus pulmonarius

AIMS

To know the ultrastructural and biochemical differences of vegetative hyphae and fruit body initials in colonies of Pleurotus pulmonarius.

METHODS AND RESULTS

Feulgen reagent was used to detects differentiation of hyphae. The intracellular laccases, proteases and beta-1,3-glucanases activity, content of cytoplasmic protein, glycogen and glucans in the cell wall were evaluated in hyphae of fruit body initials and in vegetative hyphae. The thickness of hyphal walls of the vegetative hyphae was also evaluated. Substantial biochemical changes were observed in hyphae of different zones of the fruiting colony. Hyphae at the periphery had thinner walls than in the centre of the colony.

CONCLUSION, SIGNIFICANCE AND IMPACT OF THE STUDY

Staining correlated with the enzymatic activity, protein, glycogen and glucans, in mycelium and in fruit body initials. The implications are that hyphal maturity in P. pulmonarius involves storage of glucans, in part at least, in the form of a thickened hyphal wall.

Levetiracetam prevents changes in levels of brain-derived neurotrophic factor and neuropeptide Y mRNA and of Y1- and Y5-like receptors in the hippocampus of rats undergoing amygdala kindling: implications for antiepileptogenic and mood-stabilizing properties

The amygdala-kindling model has been proposed as a model of sensitization processes with relevance to epilepsy as well as affective disorders. Levetiracetam is a novel anticonvulsant drug that delays the process of kindling, i.e., possesses antiepileptogenic properties. Preliminary reports also suggest a mood-stabilizing potential for levetiracetam. Brain-derived neurotrophic factor (BDNF) and neuropeptide Y (NPY) are central modulators of seizure activity, which undergo plastic changes during kindling epileptogenesis. Consequently, we investigated the regulation of BDNF and NPY mRNA and Y1-, Y2-, and Y5-like receptor binding in the hippocampus of vehicle-pretreated, partially and fully amygdala-kindled rats and corresponding levetiracetam-pretreated rats (40 mg/kg i.p.). The present data indicate that the process of kindling is associated with an upregulation of hippocampal BDNF and NPY mRNA levels and downregulation of Y1- and particularly Y5-like receptors. Pretreatment with levetiracetam markedly delays the progression of kindling and, in addition, exhibits a clear anticonvulsant effect. These effects are associated with abolition of the kindling-induced rise in BDNF and NPY mRNA and increasing levels of Y1- and particularly Y5-like receptors in all hippocampal subfields. Lastly, the present study reveals that an identical dose of levetiracetam reduced immobility in the rat forced swim test, the first experimental evidence indicative of an antidepressant and/or mood stabilizer-like profile of this drug. Considering that animal depression models display impairments in hippocampal NPY systems that become normalized following mood-stabilizing treatment, and that exogenous NPY exerts anticonvulsant as well as antidepressive-like activity in rodents, it is a heuristic possibility that increased hippocampal excitability and affective symptomatology may converge on an impaired hippocampal NPY function. Speculatively, the ability of levetiracetam to increase hippocampal Y1- and Y5-like receptor levels may have implications for the antiepileptic properties of levetiracetam, as well as its purported mood-stabilizing properties.

R-citalopram functionally antagonises escitalopram in vivo and in vitro: evidence for kinetic interaction at the serotonin transporter

1. Clinical observations with the selective serotonin reuptake inhibitor (SSRI), S-citalopram, indicate that S-citalopram is more efficacious and produces earlier symptom relief than RS-citalopram. Since R-citalopram is at least 20-fold weaker than S-citalopram as inhibitor of the 5-HT transporter (SERT) in preclinical studies, the clinical data suggest an unexpected antagonistic interaction between the two enantiomers. We therefore characterised the interaction of R- and S-citalopram with the SERT in in vivo and in vitro assays. 2. In both behavioural (potentiation of 5-hydroxytryptophan (5-HTP)-induced behaviour) and electrophysiological studies (inhibition of 5-HT-elicited ion currents in Xenopus oocytes expressing the human SERT (hSERT) R-citalopram inhibited the effects of S-citalopram in a dose-dependent manner. With S-citalopram : R-citalopram ratios of 1 : 2 and 1 : 4, 5-HTP potentiation was significantly smaller than with S-citalopram alone. 3. R-citalopram did not antagonise the effects of another SSRI (fluoxetine) in either behavioural or electrophysiological studies. 4. In oocytes, inhibition of hSERT-mediated currents by R-citalopram was almost completely reversible and characterised by fast on- and off-sets of action. In contrast, the off-set for S-citalopram was 35-fold slower than for R-citalopram. 5. Kinetic analysis of the oocyte experiments suggests that S-citalopram binding to SERT induces a long-lasting, inhibited state of the transporter and that coapplication of R-citalopram partially relieves SERT of this persistent inhibition. 6. We propose that the kinetic interaction of R- and S-citalopram with SERT is a critical factor contributing to the antagonistic effects of R-citalopram on S-citalopram in vitro and in vivo.

Selectivity of (3)H-MADAM binding to 5-hydroxytryptamine transporters in vitro and in vivo in mice; correlation with behavioural effects

1. Binding of the novel radioligand (3)H-2-(2-dimethylaminomethyl-phenylsulphanyl)-5-methyl-phenylamine ((3)H-MADAM) to the serotonin transporter (SERT) was used to characterise a range of selective serotonin re-uptake inhibitors (SSRIs) in vitro and in vivo. 2. (3)H-MADAM bound with high affinity in a saturable manner to both human SERT expressed in CHO cells (K(d)=0.20 nm (pK(d)=9.74+/-0.12), B(max)=35+/-4 fmol mg(-1) protein) and mouse cerebral cortex membranes (K(d)=0.21 nm (pK(d)=9.66+/-0.10), B(max)=50+/-24 fmol mg(-1) protein). 3. Binding of (3)H-MADAM was highly selective for SERT in vitro as demonstrated by the in vitro profile of MADAM tested at 75 different receptors, ion channels and transporters. This was further substantiated by the pharmacological profile of the binding. Hence, the binding of (3)H-MADAM was potently inhibited by SSRIs but not by selective inhibitors of noradrenaline transport and dopamine transport. Likewise, a 5-HT(2A/2C) receptor antagonist did not inhibit (3)H-MADAM binding. 4. (3)H-MADAM binding in vivo was inhibited only by compounds which also inhibited the binding of (3)H-MADAM in vitro (the SSRIs, mixed SERT/noradrenaline transport inhibitors and clomipramine), confirming the selectivity of (3)H-MADAM for SERT also in vivo. Moreover, compounds effective in inhibiting (3)H-MADAM binding were the only ones found to be active in the mouse 5-HTP potentiation test confirming the model as a behavioural correlate to in vivo 5-HT uptake. 5. Finally, it was found that a SERT occupancy of 85-95% was necessary to produce 50% of the maximum behavioural response (ED(50)).

Comparison between cardiac output measured by the pulmonary arterial thermodilution technique and that measured by the femoral arterial thermodilution technique in a pediatric animal model

This study compares the correlation between two methods for the determination of cardiac output-the pulmonary arterial thermodilution technique using the Swan-Ganz catheter and the femoral arterial thermodilution technique using a pulse contour analysis computer (PiCCO) catheter. We performed a prospective animal study using 16 immature Maryland pigs weighing 9 to 16 kg. A 5.5- or 7.5-Fr Swan-Ganz catheter was introduced into the femoral or jugular vein, and a 4- or 5-Fr arterial PiCCO catheter was introduced into the femoral artery. In each animal, we made measurements of cardiac output at 30-minute intervals, simultaneously by pulmonary arterial thermodilution and femoral arterial thermodilution, before, during, and after hemodiafiltration carried out via different venous catheters, recording a total of 78 measurements. The mean Swan-Ganz cardiac output was 2.22 +/- 0.94 L/min, and mean PiCCO cardiac output was 1.94 +/- 0.80 L/min (no significant difference). The mean difference (bias) of differences (limits of agreement) was 0.2812. The differences between the methods increased with higher cardiac output, but the percentage differences in relation to cardiac output remained stable. Good correlation was found between the two methods: single-measure intraclass correlation was 0.8892 (95% confidence interval, 0.54-0.95). There were no differences between the 5.5- and 7.5-FR Swan-Ganz catheters or between the 4- and 5-Fr PiCCO catheters. Femoral arterial thermodilution cardiac output measurements correlated well with pulmonary arterial thermodilution cardiac output measurements in a pediatric animal model.

Síndrome hemofagocítico y linfoma cutáneo de células T

Haemophagocytic syndrome is a rare disorder of immune regulation. Clinical features are fever, haemophagocytosis, hepatosplenomegaly, pancytopenia, lymph nodes enlargement, hypertriglyceridaemia and coagulopathy. Systemic findings may also include pulmonary infiltrates, renal failure and an inappropriate antidiuretic state. It has been described associated to many diseases, like lymphomas, most of them T-cell lymphomas, infections and systemic diseases, among other entities. Haemopoietic cells are actively ingested by monocytes and macrophages in lymph nodes, bone marrow, liver and spleen. This is a diagnostic criteria for haemophagocytic syndrome. The treatment of haemophagocytic syndrome is difficult and requires intensive supportive therapy, treatment of coagulopathy disorders, high-dose corticosteroids and immunosuppressive treatment, although in most cases there is no response to treatment and the evolution is fatal. The T-cell lymphomas that involve subcutaneous tissue and simulate panniculitis are classified recently as primary cutaneous T-cell lymphomas, and their presentation as inflammatory nodules of the legs are uncommon.

R-citalopram inhibits functional and 5-HTP-evoked behavioural responses to the SSRI, escitalopram

Escitalopram mediates the serotonin re-uptake inhibitory and antidepressant effect of citalopram racemate. However, recent studies have shown that R-citalopram inhibits the escitalopram-induced increase of extracellular 5-HT levels in the frontal cortex of rats. Here, we investigated the inhibitory effect of R-citalopram on the escitalopram-induced increase of 5-HT neurotransmission at the behavioural [potentiation of 5-hydroxytryptophan (5-HTP)-induced behavioural changes in mice and rats] and functional (increase in serum corticosterone in rats) levels. The effect of escitalopram was inhibited by R-citalopram in all three models, and R-citalopram, given alone, was inactive. The effects were more pronounced using an escitalopram to R-citalopram ratio of 1:4 than ratios of 1:2 and 1:1, suggesting a dose-dependent effect. The ED(50)-value of escitalopram in mouse 5-HTP potentiation studies corresponded to a serum concentration of approximately 50 ng/ml, which can be considered to be in the range of clinically relevant serum concentrations. In conclusion, R-citalopram inhibited the escitalopram-induced increase of 5-HT activity in functional, as well as behavioural, animal models. The mechanism involved in this interaction is currently unknown, but may be related to an improved clinical effect seen with escitalopram in comparison with citalopram.

R-citalopram counteracts the antidepressant-like effect of escitalopram in a rat chronic mild stress model

The selective serotonin (5-HT) reuptake inhibitor, citalopram, is a racemic mixture of the stereoisomers, S-(+)-citalopram (escitalopram) and R-(-)-citalopram (R-citalopram). R-citalopram has been shown to counteract the 5-HT enhancing properties of escitalopram in acute studies in animals. In the present study we report, for the first time, on an interaction between R-citalopram and escitalopram after repeated dosing in a rat chronic mild stress (CMS) model of depression. The effect of escitalopram (2.0, 3.9 and 7.8 mg/kg per day), R-citalopram (7.8 mg/kg per day) and escitalopram 3.9 mg/kg per day plus R-citalopram 7.8 mg/kg per day were studied and compared to the effect of citalopram (8.0 mg/kg per day), imipramine and R-fluoxetine (8.9 mg/kg per day). Significant effects relative to a vehicle-treated group were achieved from week 1 for escitalopram (3.9 and 7.8 mg/kg per day), from week 2 for citalopram (8.0 mg/kg per day), from week 3 for R-fluoxetine (8.9 mg/kg per day) and from week 4 for escitalopram (2.0 mg/kg per day) and imipramine (8.9 mg/kg per day). R-citalopram (7.8 mg/kg per day) and escitalopram (3.9 mg/kg per day) plus R-citalopram (7.8 mg/kg per day) did not differ significantly from vehicle. There were no drug-induced effects in non-stressed control groups. In conclusion, escitalopram showed a shorter time to response in the rat CMS model of depression than citalopram, which was faster acting than R-fluoxetine and imipramine. R-citalopram counteracted the effect of escitalopram. The mechanism of action of R-citalopram is, at the moment unclear, but may be relevant to the improved clinical antidepressant activity seen with escitalopram in comparison with citalopram, and may also indicate an earlier response to escitalopram compared to other selective serotonin reuptake inhibitors (SSRIs).

Anticonvulsant and antiepileptogenic effects of GABAA receptor ligands in pentylenetetrazole-kindled mice

Although animal models based on pentylenetetrazole (PTZ) are widely used, the mechanism by which PTZ elicits its action is not very well understood. At the molecular level, a generally accepted mechanism of PTZ is noncompetitive antagonism of the gamma-aminobutyric acid (GABA)(A) receptor complex. By a systematic pharmacological investigation of various GABA(A) receptor ligands, our aim was to gain a better understanding of the GABAergic mechanisms involved in different PTZ-induced seizures. We investigated anticonvulsant effects of various specific GABA(A) receptor ligands, which are believed to bind to different binding sites on the GABA(A) receptor complex, on PTZ-induced clonic seizures in drug naive and PTZ-kindled mice as well as their effects on the development of PTZ kindling. Diazepam and alphaxalone produced potent anticonvulsant effects and completely suppressed the development of kindling. In contrast, the antagonists bicuculline and dehydroepiandrosterone sulfate (DHEAS) displayed neither anticonvulsant nor antiepileptogenic effects. Flumazenil, often used as a reference antagonist at the GABA(A) receptor benzodiazepine (BZ) binding site, lacked anticonvulsant effects but surprisingly inhibited the development of PTZ-kindled seizures. The agonist 4,5,6,7-tetrahydroisoxazolo-(5,4-c)pyridin-3-ol (THIP) was devoid of both anticonvulsant and antiepileptogenic effects. Marked differences in drug sensitivity were observed between models based on single and chronic administration of PTZ showing that the two sets of models are fundamentally different. These results describe the pharmacology of a set of ligands believed to bind to different sites at the GABA(A) receptor complex in animal models based on PTZ and demonstrate that a drug's action in these models cannot be readily explained by agonistic or antagonistic properties at the receptor level.

Physiology of a colony of Pleurotus pulmonarius grown on medium overlaid with a Cellophane membrane

The physiology of a colony of Pleurotus pulmonarius grown on potato dextrose agar overlaid with a Cellophane membrane (PDA-WC) was studied. On PDA-WC, the colony presented higher biomass density and productivity of fruit body formation (4.84+/-0.23 mg mycelial biomass/cm2 and 23.7+/-3.12 microg ml(-1) h(-1), respectively) than that which developed on potato dextrose agar without Cellophane (PDA-OC; 0.26+/-0.01 mg mycelial biomass/cm2 and 10.8+/-1.57 microg ml(-1) h(-1), respectively). In cultures developed on PDA-WC, intracellular laccases and beta-1,3-glucanases activities were lower [12+/-0.9 arbitrary units (AU)/g mycelial biomass and 1.33+/-0.1 international units (IU)/g mycelial biomass, respectively] than those observed on PDA-OC (20.65+/-1.0 AU/g mycelial biomass and 3.67+/-0.2 IU/g mycelial biomass, respectively). In cultures developed on PDA-WC, intracellular protein and glycogen concentrations were lower (1.9+/-0.9 and 117+/-3.5 mg/g mycelial biomass, respectively) than those observed on PDA-OC (14.3+/-1.1 and 347+/-2.9 mg/g mycelial biomass, respectively). The radial growth rate and the content of glucans in the cell wall were not significantly different between cultures developed on PDA-WC and PDA-OC. These results show that the use of the Cellophane as a tool to study in vitro fungal physiology might affect the interpretation of experimental results, since the physiology under otherwise similar conditions was different on medium with and without Cellophane.

Assessment of thiamin (vitamin B1) and riboflavin (vitamin B2) status in an adult Mediterranean population

The aim of the present study was to assess the nutritional status for thiamin (vitamin B1) and riboflavin (vitamin B2) in an adult Mediterranean population, in order to identify patterns of intake, groups at risk for deficiency and factors that might influence this risk. A cross-sectional survey was carried out in Andalusia, a western Mediterranean region in southern Spain. Nutrient intakes were studied in a random sample of 3390 subjects (1746 men, 1644 women) who were between 25 and 60 years of age. Blood samples were obtained for biochemical assays in a random subsample of 372 subjects (181 men, 191 women). Food consumption was assessed by 48 h recall. Vitamin B1 and B2 were measured as erythrocyte transketolase and as erythrocyte glutathione reductase activation coefficients, respectively. Energy and vitamin intakes were significantly higher in men than in women. Intakes were below two-thirds of the recommended dietary allowance for vitamin B1 in 7.80 % of the men and 4.50 % of the woman, and were below this level for vitamin B2 in 18.00 % of the men and 11.70 % of the women. Age, educational level, alcohol use and smoking were also associated with differences in the intake of these nutrients. Biochemical analyses showed that vitamin B1 and B2 status was deficient in 6.40 and 5.30 % of the population, respectively. Although factors such as gender, age, level of education, drinking and smoking can have an effect on the risk of inadequate intake of these nutrients, these factors did not affect biochemical indices of nutritional status in the present study.

The R-enantiomer of citalopram counteracts escitalopram-induced increase in extracellular 5-HT in the frontal cortex of freely moving rats

The selective serotonin (5-HT) reuptake inhibitor, citalopram, is a racemic mixture of an S(+)- and R(-)-enantiomer, escitalopram and R-citalopram, respectively. The present study compares the effects of escitalopram, R-citalopram and citalopram on extracellular levels of 5-HT in the frontal cortex of freely moving rats. In addition, co-injection of escitalopram and R-citalopram (ratios 1:2 and 1:4) were assessed. In some experiments escitalopram and R-citalopram were infused into the frontal cortex by reverse microdialysis. Finally, the extracellular level of escitalopram in the frontal cortex was studied after administration of escitalopram alone or in combination with R-citalopram. Escitalopram (1.0-3.9 mg/kg, s.c.) produced a greater maximal increase in extracellular 5-HT than citalopram (2.0-8.0 mg/kg, s.c.). R-citalopram (15.6 mg/kg s.c.) did not affect the 5-HT levels. When co-injected, R-citalopram counteracted the escitalopram-induced increase in extracellular 5-HT levels. Local infusion of the two enantiomers into the frontal cortex produced a similar inhibitory response. R-citalopram did not influence the extracellular levels of escitalopram and therefore does not exert its effect via a pharmacokinetic interaction with escitalopram. In conclusion, the 5-HT-reuptake inhibitory activity of citalopram resides in escitalopram, and the R-enantiomer counteracts this effect. This observation would predict an improved clinical profile of escitalopram compared to citalopram.

A needleless closed system device (CLAVE) protects from intravascular catheter tip and hub colonization: a prospective randomized study

Hub colonization and subsequent intraluminal progression due to frequent opening and manipulation of intravenous systems is the cause of many catheter-related infections (CRI). A prospective, comparative, randomized study was performed to assess a new closed-needleless hub device (CLAVE) compared with conventional open systems (COS). End-points were hub and skin colonization, catheter tip colonization, catheter-related bloodstream infection (CRBSI) and number of accidental needlesticks. All cultures were processed following standard semiquantitative microbiological techniques. The study involved patients who underwent heart surgery over an 11-month period in a post-surgical ICU. During the study period, 352 patients underwent major heart surgery and 1774 catheters were inserted. Overall, 865 catheters in 178 patients were allocated to the CLAVE system and 909 catheters in 174 patients to COS. The groups were similar regarding underlying conditions and risk factors for infection. Comparison of endpoint results in CLAVE and COS groups was as follows: incidence density per 1000 catheter-days of tip colonization: 59.2 versus 83.6 (P=0.003); of hub colonization: 7.56 versus 24.66 (P=0.0017); of skin colonization: 41.5 versus 58.9 (P=0.038); and of CRBSI 3.78 versus 5.89 (P=0.4). There was one accidental needlestick and one catheter-related prosthetic endocarditis in the COS group. Multivariate analysis showed that CLAVE use was an independent protective factor for tip colonization. CLAVE offered significant protection from catheter-tip and hub colonization.

Determination of Nitroaromatic Compounds in Air Samples at Femtogram Level Using C18 Membrane Sampling and On-Line Extraction with LC−MS

This paper explores the use of C18 solid-phase extraction membranes for sampling very low concentrations of nitroaromatic compounds in the atmosphere. After sampling, analytes trapped in the membrane are desorbed on-line directly by a chromatographic mobile phase. The analytes are then separated onto a porous graphitic carbon (PGC) HPLC column. Finally, they are analyzed by an LC-MS/MS detector equipped with an atmospheric pressure chemical ionization (APCI) interface. The method was validated by controlled exposure of the membranes to standard gaseous mixtures of 2,4,6-trinitrotoluene (TNT) and 2,4-dinitrotoluene (2,4-DNT). The developed method was fully characterized, and no breakthrough was observed when sampling volumes up to 9.2 m3. Analyses of membranes following medium- and long-term storage demonstrated that samples could be stored on the C18 membranes without degradation or losses. In addition, the results obtained with this technique were compared with those obtained by a gas chromatographic method in which analytes were collected on Tenax TA and thermally desorbed. The developed method allows sampling at flow rates of 15 L/min and has method detection limits in the femtogram/liter range, with a relative standard deviation lower than 10%. An additional advantage of this method is that it separates most of the TNT and DNT isomers, as demonstrated by applying the method to the analysis of headspace over military-grade TNT explosives.

R-citalopram counteracts the effect of escitalopram in a rat conditioned fear stress model of anxiety

S-citalopram (escitalopram) mediates the serotonin reuptake inhibitory effect of the racemate, R,S-citalopram. The effect of escitalopram (0.5-3.9 mg/kg) was investigated in a rat conditioned fear stress model of anxiety and compared to the effects of R-citalopram (1.0-7.8 mg/kg), R,S-citalopram (4.0 and 8.0 mg/kg), and escitalopram (2.0 mg/kg)+R-citalopram (7.8 mg/kg). Diazepam (0.95 mg/kg) and buspirone (4.6 mg/kg) were included as positive controls. During an acquisition session, rats were allowed to freely explore a novel cage for 9 min. During that time, they received two inescapable footshocks through an electrifiable grid floor. Groups of nonshocked control rats were run in parallel. During an expression session on the next day, rats were treated with drug or vehicle 30 min before they were reintroduced into the test cage for a 9-min period this time without receiving footshocks and the total distance travelled was recorded. The distance travelled by vehicle-treated rats was markedly suppressed compared to a vehicle-treated group of nonshocked controls. Escitalopram produced a dose-dependent inhibition of the conditioned suppression of exploratory behaviour (minimal effective dose 1.0 mg/kg). Interestingly R,S-citalopram 4.0 and 8.0 mg/kg produced significantly smaller effect than escitalopram 2.0 and 4.0 mg/kg, receptively. R-citalopram, 7.8 mg/kg, produced a significant effect. However, in spite of this, R-citalopram (7.8 mg/kg) significantly inhibited the effect of escitalopram (2.0 mg/kg). The activity in drug-treated nonshocked groups was similar to the vehicle-treated group, except for the buspirone-treated group where a significant reduction was observed. The finding that R-citalopram inhibits the effect of escitalopram may be relevant to the improved clinical efficacy seen with escitalopram compared to R,S-citalopram in the treatment of anxiety and depression.

Vitamins B6 and B12 and folate status in an adult Mediterranean population

OBJECTIVE

To assess the nutritional status for vitamins B(6) and B(12) and folate in an adult Mediterranean population, in order to identify patterns of intake, groups at risk for deficiency, and factors that might influence this risk.

DESIGN

A cross-sectional epidemiological survey.

SETTING

Andalusia, a western Mediterranean region in southern Spain.

SUBJECTS

The study was carried out with a random sample of 3528 subjects (1813 men, 1715 women) who were between 25 and 60 y of age. Blood samples were obtained for biochemical assays in a random subsample of 384 subjects (183 men, 201 women).

INTERVENTIONS

Food consumption was assessed by 48-h recall. Vitamin B(6) was measured as alpha erythrocyte aspartate aminotransferase activation coefficient (alphaEAST); vitamin B(12) and folate concentrations were measured in plasma.

RESULTS

Energy and vitamin intakes were significantly higher in men than in women. In men, intakes were below two-thirds of the RDA in 10.8, 2.9 and 22.6% for B(6), B(12) and folate, respectively. The corresponding figures in women were 16.7, 5.1 and 23.5% for vitamins B(6), B(12) and folate. Age, place of residence and educational level, alcohol use and smoking were also associated with differences in the intake of these nutrients. Biochemical analyses showed that vitamins B(6), B(12) and folate status was acceptable in 75.7, 89.1 and 57.6% of the population, respectively. Plasma concentration of folate was significantly higher in women.

CONCLUSION

Our results provide a precise estimate of the nutritional status for vitamins B(6), B(12) and folate in the adult population of southern Spain. Factors such as age, place of residence, level of education and smoking can increase the risk of inadequate intake of some nutrients. However, these factors did not affect biochemical indexes of nutritional status in the present study.

SPONSORSHIP

Dirección General de Salud Pública and the Health Council of the Andalusian Regional Government.

Escitalopram, the S-(+)-enantiomer of citalopram, is a selective serotonin reuptake inhibitor with potent effects in animal models predictive of antidepressant and anxiolytic activities

OBJECTIVE

The pharmacological profile of escitalopram, the S-(+)-enantiomer of citalopram, was studied and compared with citalopram and the R-(-)-enantiomer, R-citalopram.

METHODS

Inhibition of the serotonin transporter (5-HTT) was studied in COS-1 cells expressing the human 5-HTT (h-5-HTT) and in rat brain synaptosomes. In vitro selectivity was studied relative to noradrenaline transporter (NAT) and dopamine transporter (DAT) function in rat brain synaptosomes, and affinities for other binding sites were determined. In vivo 5-HT activity was measured as inhibition of neuronal firing rate in rat dorsal raphe nucleus (DRN) and enhancement of 5-hydroxytryptophan (5-HTP)-induced behaviour (mouse and rat). Furthermore, studies were conducted in models of antidepressant (mouse forced-swim test), anxiolytic [foot-shock-induced ultrasonic vocalization (USV) in adult rats and mouse black and white box] and anti-aggressive activity (socially isolated mice).

RESULTS

Escitalopram inhibited 5-HTT functions approximately 2 times more potently than citalopram and at least 40 times more potently than R-citalopram. Escitalopram showed insignificant activity at other monoamine transporters and 144 other binding sites. Escitalopram inhibited 5-HT neuronal firing in DRN and potentiated 5-HTP-induced behaviours more potently than citalopram; R-citalopram was inactive. Escitalopram and citalopram, but not R-citalopram, reduced forced-swimming-induced immobility and facilitated exploratory behaviour in the black and white box. Escitalopram and citalopram inhibited USV potently; R-citalopram was several times less potent. Escitalopram, citalopram and R-citalopram inhibited aggressive behaviour weakly. Escitalopram and citalopram had very potent anti-aggressive effects when co-administered with l-5-HTP.

CONCLUSION

Escitalopram is a very selective 5-HT reuptake inhibitor. It is more potent than its racemate citalopram and is effective in animal models predictive of antidepressant and anxiolytic activities.

Oral and vaginal misoprostol 800 microg every 8 h for early abortion

The objective of the study was to evaluate the efficacy and safety of 800 microg misoprostol (Cytotec) every 8 h for 24 h for pharmacological abortion; the treatment was repeated if abortion did not occur in the first 24-h interval. The first misoprostol doses were always self-administered into the vagina; the second and third doses could be administered orally or vaginally depending on the amount of bleeding. Four-hundred and fifty-two women with gestations between 36 and 63 days were recruited into the study. The main outcomes assessed were: successful abortion (complete abortion without surgery), side effects, mean drop in hemoglobin, vaginal bleeding and mean time of return of menstruation. Complete abortion occurred in 409/452 (90.5%; 95% confidence interval [CI] 87%, 93%) patients. Medication to relieve symptoms was administered to all women before the first misoprostol dose. Vaginal bleeding lasted 15.9 +/- 4.4 days. The mean drop in hemoglobin, measured 14 days after abortion, was statistically significant (p = 0.0001) but without clinical relevance. According to the results obtained, 800 microg of misoprostol administered every 8 h for 24 h could be a valid method for abortion for up to 9 weeks of gestation.

Rapid serological profiling by enzyme-linked immunosorbent assay and its use as an epidemiological indicator of foot-and-mouth disease viral activity

Frequency distribution of reactivity levels of foot-and-mouth disease infection-specific antibodies in livestock populations was analysed. Specific antibody responses against non-capsid polyprotein 3ABC were assessed through a highly sensitive indirect enzyme-linked immonosorbent assay (I-ELISA 3ABC). A graphic display of data was designed based on three negative and three positive categories to illustrate reactivity patterns. The resulting patterns were correlated to the epidemiological status. On this basis, results of over 100,000 sera derived from cattle populations in regions with various well-documented epidemiological situations were compiled and are exemplified in this paper.Distinct distributions of antibody reactivity patterns reflecting the various epidemiological situations were attained. Whereas non-affected areas presented a rather homogenous negative pattern with very limited test-positive reactions, affected regions revealed quite heterogeneous profiles, including positive and negative categories, with distributions that varied according to the region. The use of graphic prints encompassing I-ELISA 3ABC antibody profile responses constituted an adequate epidemiological indicator of the risk of foot-and-mouth disease viral activity, providing immediate visualization for a rapid inference of the epidemiological situation of a region. Moreover, such profiles allowed for convenient follow-up of infection after a focus as a function of time and geographical spread.

Early detection of PrPres in BSE-infected bovine PrP transgenic mice

Transgenic mouse lines expressing different levels of the bovine prion protein gene (boPrP(C)) were generated. Upon infection with BSE prions, all transgenic lines tested exhibited characteristics of the bovine disease. Typical CNS spongiform degeneration was observed by histopathology and presence of PrP(res) could be detected both by Western blot and immunohistochemistry (IHC) assays, confirming for this model the absence of an interspecies barrier to BSE infection. Differences in incubation times post-inoculation depend upon the expression level of boPrP(C) and the amount of prions in the inoculum. In the absence of clinical signs, pathognomonic markers of disease could be detected as early as 150 or 196 days post-inoculation by IHC and Western blot analysis, respectively. This result indicates that prion infectivity in experimental mouse bioassays can be measured earlier by assessing immunologically the presence of PrP(res) in brains from inoculated animals. Although these transgenic mice were also susceptible to sheep scrapie prion infection, the extent of incubation times was considerably longer and PrP(res) was detected in only 70 % of inoculated mice. Interestingly, transgenic mice-propagated sheep scrapie prions displayed distinct biochemical properties when compared to both the original sheep scrapie and transgenic mouse-propagated BSE inoculum.

Effects of acute and chronic administration of selective monoamine re-uptake inhibitors in the rat forced swim test

The rat forced swim test (FST) is a model that is used extensively as a screening test for antidepressant activity. It has previously been reported that thorough analysis of behaviour in this model reveals two distinct types of active response - climbing and swimming - and that these are separately evoked by re-uptake inhibitors selective for noradrenaline (NA) and serotonin (5-HT), respectively. In the present study, utilising re-uptake inhibitors selective for NA, talsupram, and 5-HT, 5-chloro-1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)- phthalan (Lu 10-134-C), we examined if this scoring technique could detect the antidepressant potential of a selective serotonin re-uptake inhibitor (SSRI), and whether re-uptake inhibitors selective for distinct monoamine systems induce exclusive behavioural responses. We also analysed if chronic antidepressant administration for three weeks was more effective than acute treatment. We found Lu 10-134-C (40 mg/kg; PO) to be behaviourally active in this paradigm. Although treatment with talsupram (40 mg/kg; PO) resulted solely in climbing behaviour, Lu 10-134-C induced both climbing and swimming behaviour. However, chronic pre-treatment with either re-uptake inhibitor (20 mg/kg; twice daily; PO) failed to augment the response observed with acute treatment. Similarly, chronic administration of either compound was without effect on the basal, or stress-induced, serum corticosterone concentrations or anterior pituitary (AP) preproopiomelanocorticotropin (POMC) mRNA expression. These results suggest that selective monoamine re-uptake inhibition produces distinct, but not necessarily exclusive, behavioural responses in the forced swim test.

R-citalopram attenuates anxiolytic effects of escitalopram in a rat ultrasonic vocalisation model

Escitalopram mediates the serotonin reuptake inhibitory effect of citalopram. To investigate the potential interactive effects between escitalopram and R-citalopram, they were studied at standard and elevated serotonin levels in a model predictive of anxiolytic activity (inhibition of footshock-induced ultrasonic vocalisation in adult rats). At standard levels, citalopram partially inhibited (64%) and escitalopram abolished (97%) vocalisation. Co-treatment with L-5-hydroxytryptophan resulted in complete inhibition with citalopram and a substantially enhanced response to escitalopram, while R-citalopram increased the vocalisation significantly. Furthermore, R-citalopram attenuated the effect of escitalopram. These findings may be relevant to the enhanced clinical efficacy seen with escitalopram compared to citalopram.

Stress-induced vocalisation in adult animals. A valid model of anxiety?

The post-stimuli anticipatory vocalisations that follow stressful and painful conditions are suggested as a quantitative measure of the emotional state of fear and anxiety in animal models. Adult rats emit characteristic 22-kHz ultrasound vocalisations consisting of 20-30 kHz calls with a mean duration of 300-600 ms as response to aversive stimuli (e.g. inescapable electric footshock, acoustic or air-puff stimuli, agonistic encounter or withdrawal from treatment with drugs of abuse). The vocalisations are accompanied by defensive submissive behaviour and signal a refractory, socially withdrawn or helpless state. Furthermore, brain structures that are involved in the mediation of anxiety-like behaviour, e.g. the dorsal periaqueductal grey and cortical areas, are also important for modulation of ultrasonic vocalisation. Benzodiazepines, e.g. diazepam, inhibit shock-induced ultrasonic vocalisation although the active doses are generally close to those that produce sedation and muscle relaxation. Selective serotonin reuptake inhibitors and other antidepressants that preferentially enhance serotonergic neurotransmission inhibit footshock-induced ultrasonic vocalisation. The 5-HT(2) receptor antagonistic properties of fluoxetine may explain why only partial inhibition is achieved. The biphasic dose-response curve of the racemic drug, citalopram, may perhaps be ascribed to an attenuating effect of R-citalopram. Tricyclic antidepressants, e.g. imipramine, and antidepressants that preferentially enhance catecholaminergic neurotransmission, e.g. reboxetine and venlafaxine, are inactive. Classical antipsychotics like haloperidol have no or a weak inhibitory effect. Serotonin plays a major role in the mediation of ultrasonic vocalisation, and in particular 5-HT(1A) and 5-HT(2) receptors are found to have a prominent role. Different serotonergic pathways are likely to be involved in the mediation of the anxiolytic-like response, e.g. the pathway ascending from the dorsal raphe nucleus through the medial forebrain bundle to the amygdala and frontal cortex mediating conditioned/learned anxiety and another pathway ascending from the dorsal raphe nucleus to the periaqueductal grey mediating unconditioned/fight flight anxiety. Dopamine D(2) receptor agonists are potent inhibitors of footshock-induced ultrasonic vocalisation. The role of dopamine D(1) receptors and adrenoceptors remains to be further elucidated. Several other neurotransmitters are involved in the mediation of ultrasonic vocalisation, e.g. acetylcholine, histamine and glutamate. There is also a need for further studies of how changes in stress-axis function may modulate ultrasonic vocalisation and for studies of the effects of chronic drug treatment on ultrasonic vocalisation.

Effect of a yellow filter on mesopic contrast perception and differential light sensitivity in the visual field

PURPOSE

Previous studies on the effects of yellow filters in the visual performance have been carried out, presenting discrepancies among the different investigations. Our study reports the influence of the yellow filter without residual reflections on contrast perception and differential light sensitivity (DLS) under mesopic conditions.

METHODS

Contrast sensitivity, low contrast visual acuity and luminance thresholds in the central visual field (30 degrees ) were measured in a group of 38 adult subjects with and without a coated yellow lens (482-nm cut-off) under mesopic conditions.

RESULTS

The contrast sensitivity mean was significantly better with the filter at low- and middle-range spatial frequencies (1.5 cycles/degree p = 0.002 and 6 cycles/degree p = 0.02). At 5% contrast, the mesopic low contrast visual acuity improved significantly (p = 0.004) when interposing the yellow filter. The increase in DLS was statistically significant [e.g. all visual fields p = 0.0003 and macular visual field (9.5 degrees ) p = 0.00001] through the yellow filter on the different established areas of the visual field (30 degrees ).

CONCLUSIONS

The yellow filter without residual reflections had a positive influence on the brightness and contrast perception of healthy subjects, for which its use would be beneficial under mesopic conditions.

Noncataleptogenic, centrally acting dopamine D-2 and serotonin 5-HT2 antagonists within a series of 3-substituted 1-(4-fluorophenyl)-1H-indoles

A series of 1-(4-fluorophenyl)-1H-indoles substituted at the 3-position with 1-piperazinyl, 1,2,3,6-tetrahydro-4-pyridinyl, and 4-piperidinyl was synthesized. Within all three subseries potent dopamine D-2 and serotonin 5-HT2 receptor affinity was found in ligand binding studies. Quipazine-induced head twitches in rats were inhibited by most derivatives as a measure of central 5-HT2 receptor antagonism. Piperazinyl and tetrahydropyridyl indoles were cataleptogenic, while piperidyl substituted indoles surprisingly were found to be noncataleptogenic or only weakly cataleptogenic. Noncataleptogenic piperidyl derivatives also failed to block dopaminergic-mediated stereotypies, that is methyl phenidate-induced gnawing behavior in mice. These profiles resemble that of the atypical neuroleptic clozapine. 1-Ethyl-2-imidazolidinone was found to be the optimal substituent of the basic nitrogen atom in order to avoid catalepsy. The atypical neuroleptic 1-[2-[4-[5-chloro-1-(4-fluorophenyl)-1H-indol-3-yl]-1-piperidinyl] ethyl]-2-imidazolidinone (sertindole, compound 14c) was selected for further development as a result of these structure/activity studies.

Lymphoma in a rabbit: histopathological and immunohistochemical findings

Lymphoma is a very common lymphoid neoplasm in domestic animals, but few naturally occurring cases have been reported in rabbits. It presents at different sites within rabbits and, although the macroscopic pattern tends to be similar, different cell populations may be involved. This report describes a case of spontaneous lymphoma ocurring in a two-and-a-half-year-old pet Dutch dwarf rabbit. T and B lymphocyte infiltrates were observed in skin, lung, kidney, liver, intestine and lymph nodes, in each case affecting one or more tissue structures. The diagnosis, based on microscopic and immunocytochemical findings, was multicentric, T cell-rich B cell lymphoma with skin involvement.

Behavioural and biochemical studies of citalopram and WAY 100635 in rat chronic mild stress model

Reversal of chronic mild stress (CMS)-induced decrease of sucrose consumption has been studied in rats after 2, 7, 14, and 35 days treatment with imipramine, citalopram (both 10 mg/kg per day, i.p.), WAY 100635 (0.2 mg/kg sc, b.i.d.), and citalopram plus WAY 100635. Bmax, Kd, and functional status [cyclic AMP (cAMP) generation] of beta1-adrenoceptors were assessed in cortical tissue at the same time points. Citalopram reversed CMS-induced reduction of sucrose intake at an earlier time point than imipramine. WAY 100635 was not effective and did not potentiate the effect of citalopram. CMS produced increase of Bmax. Imipramine decreased Bmax in controls (Days 2, 7, 14, and 35) and normalised Bmax in stressed animals (Day 35). Citalopram, WAY 100635, and the combination increased Bmax in stressed animals and controls (Days 14 and 35). Inconsistent changes of Kd values and of cAMP responses to noradrenaline (NA) stimulation were observed. Thus stress- and drug-induced effects on beta1-adrenoceptors do not appear to be a common biochemical marker of antidepressant-like activity in the CMS model.

[Septic thrombophlebitis of the portal vein associated with reversible portal hypertension]

Septic thrombophlebitis of the portal vein is an unusual and serious complication of abdominal infection. We present a patient with thrombophlebitis of the portal vein of unknown origin, suffering from fever, abdominal pain, jaundice, abnormal liver test function and bacteremia related to Bacteroides fragilis. Ultrasonography, with doppler of the portal vein, was performed which showed thrombosis of the portal vein together with signs of portal hypertension. The patient underwent six weeks of antibiotic treatment. The evolution was favourable, the infection was overcome and the portal vein was de-obstructed as a consequence of which the signs of portal hypertension disappeared.

Microtubule-associated protein 2 phosphorylation is decreased in the human epileptic temporal lobe cortex

Microtubule-associated protein 2 (MAP2) is an abundant component of the neuronal cytoskeleton whose function is related to the outgrowth and stability of neuronal processes, to synaptic plasticity and neuronal cell death. We have sought to study whether abnormal patterns of neuronal activity which are characteristic of epileptic patients are associated to alterations of MAP2 phosphorylation. An antibody (305) that selectively recognizes a phosphorylated epitope in a proline-rich region of the MAP2 molecule has been used to analyze neocortical biopsy samples from temporal lobe epileptic patients, whose electrocorticogram activity had been previously monitored. Immunoblot analysis showed that samples with greater spiking activity displayed significantly diminished MAP2 phosphorylation. Immunocytochemical analysis revealed the occurrence of discrete areas in the neocortex with highly decreased or no immunostaining for antibody 305, which showed a clear, although non-significant, tendency to appear more frequently in areas with greater spiking activity. To further support an association between epileptiform activity and MAP2 dephosphorylation an experimental model of epileptiform activity in cultures of rat hippocampal neurons was used. Neurons were cultured during 15 days in the presence of kynurenic acid, an antagonist of glutamate receptors. At this time, kynurenic acid was removed from the culture medium and neurons developed seizure-like activity. Using antibody 305, we found a decrease of MAP2 phosphorylation that was already visible after 15 min of kynurenic acid withdrawal. We therefore propose that MAP2 phosphorylation is decreased in the neocortex of epileptic patients and that this decrease is a likely consequence of seizure activity. Also, MAP2 dephosphorylation may lead to alterations of the neuronal cytoskeleton and eventually to neuronal damage and loss, which is typical of epileptic patients.

Oral versus vaginal misoprostol for cervical priming in first-trimester abortion: a randomized trial

The objective of this study was to compare the oral and vaginal administration of misoprostol for cervical priming before surgical abortion up to 63 days' gestation. A total of 900 pregnant women, with ages ranging from 18 to 42 years, who asked for pregnancy termination, were included in this study. Women were randomly allocated to one of the following groups: oral administration of 400 microg misoprostol, 8 h before aspiration; and vaginal self-administration of 400 microg misoprostol, 4 h before aspiration. During admission, all subjects were checked on a 15-min basis. The preoperative cervical dilatation achieved was the main outcome assessed. The cervix was dilated (Hegar > or = 8) in 348 (78%) subjects from the oral treatment group and in 391 (87%) women from the vaginal treatment group; this difference was statistically significant (p = 0.0004). The mean dilatation achieved in the oral treatment group was 8.1 mm (SD 1.6 mm) and it was 8.5 mm (SD 1.5 mm) in the vaginal treatment group; this difference was statistically significant (p = 0.0001). The frequencies of side-effects such as nausea, vomiting, diarrhea and chills reported by women from the vaginal misoprostol group were 10, 8, 18 and 4 times lower, respectively, than those reported by subjects from the oral misoprostol group. In conclusion, vaginal self-administration of misoprostol was the best administration route, as it obtained the same or greater priming effectiveness of the cervix in half the time with a much lower frequency of side-effects.

First field trial of a transmissible recombinant vaccine against myxomatosis and rabbit hemorrhagic disease

As a novel approach for immunisation of wild rabbits, we have recently developed a transmissible vaccine against myxomatosis and rabbit hemorrhagic disease (RHD) based on a recombinant myxoma virus (MV) expressing the RHDV capsid protein [J. Virol. 74 (2000) 1114]. The efficacy and safety of the vaccine have been extensively evaluated under laboratory conditions. In this study, we report the first limited field trial of the candidate vaccine that was undertaken in an island of 34 Has containing a population of around 300 rabbits. Following administration by the subcutaneous route to 76 rabbits, the vaccine induced specific antibody responses against both myxomatosis and RHDV in all the inoculated rabbits. Furthermore, the recombinant virus exhibited a limited horizontal transmission capacity, promoting seroconversion of around 50% of the uninoculated rabbit population. No evidence of undesirable effects due to the recombinant virus field release was detected.

Inhibition of glioma growth in vivo by selective activation of the CB(2) cannabinoid receptor

The development of new therapeutic strategies is essential for the management of gliomas, one of the most malignant forms of cancer. We have shown previously that the growth of the rat glioma C6 cell line is inhibited by psychoactive cannabinoids (I. Galve-Roperh et al., Nat. Med., 6: 313-319, 2000). These compounds act on the brain and some other organs through the widely expressed CB(1) receptor. By contrast, the other cannabinoid receptor subtype, the CB(2) receptor, shows a much more restricted distribution and is absent from normal brain. Here we show that local administration of the selective CB(2) agonist JWH-133 at 50 microg/day to Rag-2(-/-) mice induced a considerable regression of malignant tumors generated by inoculation of C6 glioma cells. The selective involvement of the CB(2) receptor in this action was evidenced by: (a) the prevention by the CB(2) antagonist SR144528 but not the CB(1) antagonist SR141716; (b) the down-regulation of the CB(2) receptor but not the CB(1) receptor in the tumors; and (c) the absence of typical CB(1)-mediated psychotropic side effects. Cannabinoid receptor expression was subsequently examined in biopsies from human astrocytomas. A full 70% (26 of 37) of the human astrocytomas analyzed expressed significant levels of cannabinoid receptors. Of interest, the extent of CB(2) receptor expression was directly related with tumor malignancy. In addition, the growth of grade IV human astrocytoma cells in Rag-2(-/-) mice was completely blocked by JWH-133 administration at 50 microg/day. Experiments carried out with C6 glioma cells in culture evidenced the internalization of the CB(2) but not the CB(1) receptor upon JWH-133 challenge and showed that selective activation of the CB(2) receptor signaled apoptosis via enhanced ceramide synthesis de novo. These results support a therapeutic approach for the treatment of malignant gliomas devoid of psychotropic side effects.