Molecular mechanisms involved in interleukin 1-beta (IL-1β)-induced memory impairment. Modulation by alpha-melanocyte-stimulating hormone (α-MSH)

Pro-inflammatory cytokines can affect cognitive processes such as learning and memory. Particularly, interleukin-1β (IL-1β) influences the consolidation of hippocampus-dependent memories. We previously reported that administration of IL-1β in dorsal hippocampus impaired contextual fear memory consolidation. Different mechanisms have been implicated in the action of IL-1β on long-term potentiation (LTP), but the processes by which this inhibition occurs in vivo remain to be elucidated. We herein report that intrahippocampal injection of IL-1β induced a significant increase in p38 phosphorylation after contextual fear conditioning. Also, treatment with SB203580, an inhibitor of p38, reversed impairment induced by IL-1β on conditioned fear behavior, indicating that this MAPK would be involved in the effect of the cytokine. We also showed that IL-1β administration produced a decrease in glutamate release from dorsal hippocampus synaptosomes and that treatment with SB203580 partially reversed this effect. Our results indicated that IL-1β-induced impairment in memory consolidation could be mediated by a decrease in glutamate release. This hypothesis is sustained by the fact that treatment with d-cycloserine (DCS), a partial agonist of the NMDA receptor, reversed the effect of IL-1β on contextual fear memory. Furthermore, we demonstrated that IL-1β produced a temporal delay in ERK phosphorylation and that DCS administration reversed this effect. We also observed that intrahippocampal injection of IL-1β decreased BDNF expression after contextual fear conditioning. We previously demonstrated that α-MSH reversed the detrimental effect of IL-1β on memory consolidation. The present results demonstrate that α-MSH administration did not modify the decrease in glutamate release induced by IL-1β. However, intrahippocampal injection of α-MSH prevented the effect on ERK phosphorylation and BDNF expression induced by IL-1β after contextual fear conditioning. Therefore, in the present study we determine possible molecular mechanisms involved in the impairment induced by IL-1β on fear memory consolidation. We also established how this effect could be modulated by α-MSH.

Prevalence of and risk factors for oral human papillomavirus among young women in Costa Rica

BACKGROUND

Little is known about the epidemiology of oral human papillomavirus (HPV) in Latin America.

METHODS

Women (N = 5838) aged 22-29 in the control and vaccine arms of an HPV-16/18 vaccine trial in Costa Rica had oral, cervical, and anal specimens collected. Samples were tested for alpha mucosal HPV types (SPF10/LiPA25 version 1); a subset of oral samples (n = 500) was tested for cutaneous HPV types in the genera alpha, beta, gamma, mu, and nu.

RESULTS

In the control arm (n = 2926), 1.9% of women had an oral alpha mucosal HPV detected, 1.3% had carcinogenic HPV, and 0.4% had HPV-16; similar patterns for non-16/18 HPV types were observed in the vaccine arm. Independent risk factors for any oral alpha mucosal HPV among women in the control arm included marital status (adjusted odds ratio [AOR], 3.2; 95% confidence interval [CI], 1.8-5.7 for single compared to married/living as married), number of sexual partners (AOR, 2.4; 95% CI, 1.0-6.1 for ≥4 partners compared to 0-1 partners), chronic sinusitis (AOR, 3.1; 95% CI, 1.5-6.7), and cervical HPV infection (AOR, 2.6; 95% CI, 1.4-4.6). Detection of beta HPV was common (18.6%) and not associated with sexual activity.

CONCLUSIONS

Unlike cutaneous HPV types, alpha mucosal HPV types were uncommon in the oral region and were predominately associated with sexual behavior. Clinical Trials Registration. NCT00128661.

Reduced prevalence of oral human papillomavirus (HPV) 4 years after bivalent HPV vaccination in a randomized clinical trial in Costa Rica

Background

Human papillomavirus (HPV) infection, particularly with type 16, causes a growing fraction of oropharyngeal cancers, whose incidence is increasing, mainly in developed countries. In a double-blind controlled trial conducted to investigate vaccine efficacy (VE) of the bivalent HPV 16/18 vaccine against cervical infections and lesions, we estimated VE against prevalent oral HPV infections 4 years after vaccination.

Methods and Findings

A total of 7,466 women 18–25 years old were randomized (1∶1) to receive the HPV16/18 vaccine or hepatitis A vaccine as control. At the final blinded 4-year study visit, 5,840 participants provided oral specimens (91·9% of eligible women) to evaluate VE against oral infections. Our primary analysis evaluated prevalent oral HPV infection among all vaccinated women with oral and cervical HPV results. Corresponding VE against prevalent cervical HPV16/18 infection was calculated for comparison. Oral prevalence of identifiable mucosal HPV was relatively low (1·7%). Approximately four years after vaccination, there were 15 prevalent HPV16/18 infections in the control group and one in the vaccine group, for an estimated VE of 93·3% (95% CI = 63% to 100%). Corresponding efficacy against prevalent cervical HPV16/18 infection for the same cohort at the same visit was 72·0% (95% CI = 63% to 79%) (p versus oral VE = 0·04). There was no statistically significant protection against other oral HPV infections, though power was limited for these analyses.

Conclusions

HPV prevalence four years after vaccination with the ASO4-adjuvanted HPV16/18 vaccine was much lower among women in the vaccine arm compared to the control arm, suggesting that the vaccine affords strong protection against oral HPV16/18 infection, with potentially important implications for prevention of increasingly common HPV-associated oropharyngeal cancer.

ClinicalTrials.gov, Registry number NCT00128661

Long-term responders to first-line bevacizumab-based therapy among patients (pts) with HER2-negative metastatic breast cancer (MBC): Retrospective results of an ambispective observational study

e12558

Background: LORENA is an ambispective observational study evaluating B-based therapy in a real world setting which purpose is to assess clinical features, treatments and prognosis of HER2-negative MBC pts with ≥12 months (mo.) of PFS to 1st-line B-based chemotherapy (CT). Methods: Pts with MBC receiving 1st-line CT and B are enrolled. No prespecified schedules, doses or assessments. Data since the introduction of the treatment with B were collected at inclusion (retrospective phase), and prospectively at 18 mo. after enrollment for the patients alive at the time of inclusion, including B-targeted adverse events (AEs). Relevant baseline and on-study variables were analyzed by Cox model to identify independent effects on PFS. Results: By Jan 2013, complete retrospective data were available for 84 pts, 33 (39.3%) of them having stage III-IV at diagnosis. Median age, 50 years (r: 29–77); age ≥65 years, 13%; triple negative, 20.2%; bone/liver/lung metastases (%), 55/27/40; ≥2 metastases sites: 46.4%; ECOG status 0-1: 91.7%, ≥2: 5.9%, UK: 2.3%. 67% of pts have received prior (neo)adjuvant CT, with 56 and 30% of them with anthracyclines and taxanes, respectively. The objective response was 78%, including complete responses in 23%. A further 22% had stable disease. Median duration of B-based therapy was 12.4 mo. PFS events had been recorded in 44% of pts. Median PFS: 19.5 mo. (95%CI: 15.6-23.2). Cox proportional hazard multivariate regression model showed that B-based therapy ≥15 vs <15 mo was associated with improved PFS (26.5 vs 14.0 mo, p= 0.009; HR 0.40 [95%CI: 0.19-0.81]). The most common grade ≥3 B-related AEs were: Hypertension 9.5%, proteinuria 3.5%, bleeding 3.5%, and thromboembolic events 1.1%. No B-related death was reported. Conclusions: Outcomes in routine oncology practice for LORENA patients are consistent with those from prospective trials of 1st-line B-containing therapy and ATHENA study. These results suggest a benefit from a maintained VEGF suppression and that B continuation either as a single agent or combined with CT, until disease progression is recommended. Follow-up is ongoing.

Cross-protective vaccine efficacy of the bivalent HPV vaccine against HPV31 is associated with humoral immune responses: results from the Costa Rica Vaccine Trial

BACKGROUND

We investigated the role of antibody responses as potential mechanism for the cross-protective vaccine-efficacies (VE) observed from randomized clinical trials of the HPV16/18 bivalent vaccine. Results HPV31 cases had lower HPV16 antibody levels than controls (OR 4th quartile compared with 1st quartile = 0.63; 95%CI: 0.36-1.08; p-trend = 0.03). HPV31 cases were also less likely to have detectable HPV31 neutralization, and HPV16 avidity than controls. No statistically significant differences by HPV18 antibody or HPV45 neutralization were observed among HPV45 cases and controls. Protection against HPV58 was not associated with any of the markers, confirming the specificity of our findings.

METHODS

Samples are from three-dose HPV vaccine recipients from the Costa Rica HPV16/18 vaccine trial. Women with a new HPV31, HPV45, or HPV58 infections over four years of follow-up were compared with randomly selected control women--with no new infection with HPV31/45/58--with respect to HPV16 and HPV18 antibody, HPV31, HPV45, and HPV58 neutralization, and HPV16 avidity.

CONCLUSIONS

High HPV16 levels and avidity, and the ability to neutralize HPV31 were associated with protection against newly detected HPV31 infections, suggesting that the partial VE demonstrated for HPV31 is likely to be mediated at least in part through antibodies induced by HPV16/18 vaccination.

Optimizing gene transfer to conventional outflow cells in living mouse eyes

The mouse eye has physiological and genetic advantages to study conventional outflow function. However, its small size and shallow anterior chamber presents technical challenges to efficient intracameral delivery of genetic material to conventional outflow cells. The goal of this study was to optimize methods to overcome this technical hurdle, without damaging ocular structures or compromising outflow function. Gene targeting was monitored by immunofluorescence microscopy after transduction of adenovirus encoding green fluorescent protein driven by a CMV promoter. Guided by a micromanipulator and stereomicroscope, virus was delivered intracamerally to anesthetized mice by bolus injection using a 33 gauge needle attached to Hamilton syringe or infusion with glass micropipette connected to syringe pump. The total number of particles introduced remained constant, while volume of injected virus solution (3-10 μl) was varied for each method and time of infusion (3-40 min) tested. Outflow facility and intraocular pressure were monitored invasively using established techniques. Unlike bolus injections or slow infusions, introduction of virus intracamerally during rapid infusions (3 min) at any volume tested preferentially targeted trabecular meshwork and Schlemm's canal cells, with minimal transduction of neighboring cells. While infusions resulted in transient intraocular pressure spikes (commensurate with volume infused, Δ40-70 mmHg), eyes typically recovered within 60 min. Transduced eyes displayed normal outflow facility and tissue morphology 3-6 days after infusions. Taken together, fast infusion of virus solution in small volumes intracamerally is a novel and effective method to selectively deliver agents to conventional outflow cells in living mice.

HPV16 seropositivity and subsequent HPV16 infection risk in a naturally infected population: comparison of serological assays

Background

Several serological assays have been developed to detect antibodies elicited against infections with oncogenic human papillomavirus (HPV) type 16. The association between antibody levels measured by various assays and subsequent HPV infection risk may differ. We compared HPV16-specific antibody levels previously measured by a virus-like particle (VLP)-based direct enzyme-linked immunoassay (ELISA) with levels measured by additional assays and evaluated the protection against HPV16 infection conferred at different levels of the assays.

Methodology/Principal Findings

Replicate enrollment serum aliquots from 388 unvaccinated women in the control arm of the Costa Rica HPV vaccine trial were measured for HPV16 seropositivity using three serological assays: a VLP-based direct ELISA; a VLP-based competitive Luminex immunoassay (cLIA); and a secreted alkaline phosphatase protein neutralization assay (SEAP-NA). We assessed the association of assay seropositivity and risk of subsequent HPV16 infection over four years of follow-up by calculating sampling-adjusted odds ratios (OR) and HPV16 seropositivity based on standard cutoff from the cLIA was significantly associated with protection from subsequent HPV16 infection (OR = 0.48, CI = 0.27–0.86, compared with seronegatives). Compared with seronegatives, the highest seropositive tertile antibody levels from the direct ELISA (OR = 0.53, CI = 0.28–0.90) as well as the SEAP-NA (OR = 0.20, CI = 0.06, 0.64) were also significantly associated with protection from HPV16 infection.

Conclusions/Significance

Enrollment HPV16 seropositivity by any of the three serological assays evaluated was associated with protection from subsequent infection, although cutoffs for immune protection were different. We defined the assays and seropositivity levels after natural infection that better measure and translate to protective immunity.

Evaluation of the FTA carrier device for human papillomavirus testing in developing countries

Liquid-based methods for the collection, transportation, and storage of cervical cells are cumbersome and expensive and involve laborious DNA extraction. An FTA cartridge is a solid carrier device, easier to handle and allowing simple DNA elution for human papillomavirus (HPV) testing. HPV-DNA results from cervical specimens collected in PreservCyt medium (Hologic, Inc.) and the indicating FTA elute cartridge were compared in an area where transportation and storage may affect the performance of the test. Cervical cells from 319 young adult women enrolled in the Costa Rica Vaccine Trial were collected by a nurse using a Cervex brush (Roberts), which was placed on the FTA cartridge and subsequently rinsed in 20 ml of PreservCyt medium. Two 0.5-ml PreservCyt aliquots were frozen for HPV-PCR testing; the FTA cartridges were kept at room temperature. HPV-DNA detection and typing was performed using SPF(10) PCR/DEIA (DNA enzyme immunoassay detection of amplimers)/LiPA(25) system. The percent agreement, agreement among positives, and kappas were estimated. Positivity was higher for FTA compared to PreservCyt specimens (54.5% versus 45.8%, P < 0.001). For oncogenic types, the overall agreement was 0.92, the agreement between positives was 0.74, and the kappa was 0.79. For individual HPV types, the overall agreement ranged from 0.97 to 1.00. We did not observe reduced cytology adequacy when specimen collection for cytology was preceded by FTA collection for HPV testing. HPV-DNA detection from FTA cartridges is broadly comparable to detection from PC medium. The higher HPV detection observed for FTA-collected specimens should be explored further. FTA cartridges could provide a simpler and more cost-effective method for cervical cell collection, storage, and transportation for HPV-DNA detection in research settings in developing countries.

Prevalence of and risk factors for anal human papillomavirus infection among young healthy women in Costa Rica

BACKGROUND

Anal cancer is caused by human papillomavirus (HPV), yet little is known about anal HPV infection among healthy young women.

METHODS

A total of 2017 sexually active women in the control arm of an HPV-16/18 vaccine trial had a single anal specimen collected by a clinician at the 4-year study visit. Samples were tested for HPV by SPF(10) PCR/DEIA/LiPA(25), version 1.

RESULTS

A total of 4% of women had HPV-16, 22% had oncogenic HPV, and 31% had any HPV detected in an anal specimen. The prevalence of anal HPV was higher among women who reported anal intercourse, compared with those who did not (43.4% vs 28.4%; P< .001). Among women who reported anal intercourse, cervical HPV (adjusted odds ratio [aOR], 5.3 [95% confidence interval {CI}, 3.4-8.2]), number of sex partners (aOR, 2.2 [95% CI, 1.1-4.6] for ≥ 4 partners), and number of anal intercourse partners (aOR, 1.9 [95% CI, 1.1-3.3] for ≥ 2 partners) were independent risk factors for anal HPV detection. Among women who reported no anal intercourse, cervical HPV (aOR, 4.7 [95% CI, 3.7-5.9]), number of sex partners (aOR, 2.4 [95% CI, 1.7-3.4] for ≥ 4 partners), and report of anal fissures (aOR, 2.3 [95% CI, 1.1-4.8]) were associated with an increased odds of anal HPV detection.

CONCLUSION

Anal HPV is common among young women, even those who report no anal sex, and was associated with cervical HPV infection. Anal fissures in women who report never having had anal intercourse may facilitate HPV exposure.

CLINICAL TRIALS REGISTRATION

NCT00128661.

Direct comparison of HPV16 serological assays used to define HPV-naïve women in HPV vaccine trials

BACKGROUND

Two HPV serological assays, the competitive Luminex immunoassay (cLIA), and an enzyme-linked immunoassay (ELISA) against HPV16 have been used to define HPV-naïve subcohorts within large HPV vaccination trials. Some of the variation in estimated vaccine efficacies may be due to the differences in these assays used to define the HPV-naïve subgroups. To guide the interpretation of published results, we compared these assays.

METHODS

Replicate enrollment sera from a stratified sample of 388 unvaccinated women from the control arm of the Costa Rica HPV 16/18 Vaccine Trial were measured for antibodies against HPV16 using cLIA and ELISA. Agreement between the assays was estimated using standard and alternative assay cutoffs.

RESULTS

Using laboratory-determined seropositivity cutoffs, sampling-adjusted HPV16 seropositivity was 24.8% by ELISA and 7.2% by cLIA. Comparing cLIA and ELISA antibody levels based on the standard cutoffs, overall agreement was 53% (positive-agreement = 49%). The poor agreement was mainly driven by the higher sensitivity of the ELISA than cLIA, resulting in 30% of the ELISA-positive sample that were cLIA-negative (none of the ELISA-negatives were cLIA-positive). Increasing ELISA cutoff to 54 ELISA units (EU)/mL (the level which maximized agreement with cLIA; ELISA standard cutoff is 8 EU/mL) resulted in higher agreement (overall agreement = 91%; positive agreement = 78%).

CONCLUSIONS

ELISA and cLIA are different from each other based on the laboratory-determined cutoff. Increasing ELISA cutoff increased agreement with cLIA, which could facilitate comparisons among studies that use different assays.

IMPACT

Keeping cLIA at the laboratory-determined cutoff but altering ELISA cutoff for seropositivity might facilitate vaccine efficacy comparisons in the naïve cohorts defined by cLIA.

Single nucleotide polymorphisms in the PRDX3 and RPS19 and risk of HPV persistence and cervical precancer/cancer

Background

Host genetic factors might affect the risk of progression from infection with carcinogenic human papillomavirus (HPV), the etiologic agent for cervical cancer, to persistent HPV infection, and hence to cervical precancer and cancer.

Methodology/Principal Findings

We assessed 18,310 tag single nucleotide polymorphisms (SNPs) from 1113 genes in 416 cervical intraepithelial neoplasia 3 (CIN3)/cancer cases, 356 women with persistent carcinogenic HPV infection (median persistence of 25 months) and 425 randomly selected women (non-cases and non-HPV persistent) from the 10,049 women from the Guanacaste, Costa Rica HPV natural history cohort. For gene and SNP associations, we computed age-adjusted odds ratio and p-trend. Three comparisons were made: 1) association with CIN3/cancer (compared CIN3/cancer cases to random controls), 2) association with persistence (compared HPV persistence to random controls), and 3) progression (compared CIN3/cancers with HPV-persistent group). Regions statistically significantly associated with CIN3/cancer included genes for peroxiredoxin 3 PRDX3, and ribosomal protein S19 RPS19. The single most significant SNPs from each gene associated with CIN3/cancer were PRDX3 rs7082598 (P_trend<0.0001), and RPS19 rs2305809 (P_trend=0.0007), respectively. Both SNPs were also associated with progression.

Conclusions/Significance

These data suggest involvement of two genes, RSP19 and PRDX3, or other SNPs in linkage disequilibrium, with cervical cancer risk. Further investigation showed that they may be involved in both the persistence and progression transition stages. Our results require replication but, if true, suggest a role for ribosomal dysfunction, mitochondrial processes, and/or oxidative stress, or other unknown function of these genes in cervical carcinogenesis.

Impairment of lysosomal integrity by B10, a glycosylated derivative of betulinic acid, leads to lysosomal cell death and converts autophagy into a detrimental process

In this study, we report a novel mechanism of action for a cytotoxic derivative of betulinic acid (BA). B10 is a semi-synthetic glycosylated derivative of BA selected for its enhanced cytotoxic activity. Interestingly, although B10 induces apoptosis, caspase-3 downregulation incompletely prevents B10-induced cell death, Bcl-2 overexpression fails to protect cells and DNA fragmentation rates do not reflect cell death rates in contrast to cytoplasmic membrane permeabilization. These results implicate that apoptotic and non-apoptotic cell death coexist upon B10 treatment. Unexpectedly, we found that B10 induces autophagy and also abrogates the autophagic flux. B10 destabilizes lysosomes as shown by Lysotracker Red staining and by cathepsin Z and B release from lysosomes into the cytoplasm. Consistently, the cathepsin inhibitor Ca074Me significantly decreases B10-induced cell death, further supporting the fact that the release of lysosomal enzymes contributes to B10-triggered cell death. Downregulation of ATG7, ATG5 or BECN1 by RNAi significantly decreases caspase-3 activation, lysosomal permeabilization and cell death. Thus, by concomitant induction of autophagy and inhibition of the autophagic flux, B10 turns autophagy into a cell death mechanism. These findings have important implications for the therapeutic exploitation of BA derivatives, particularly in apoptosis-resistant cancers.

Preconditioning donor with a combination of tacrolimus and rapamacyn to decrease ischaemia-reperfusion injury in a rat syngenic kidney transplantation model

Reperfusion injury remains one of the major problems in transplantation. Repair from ischaemic acute renal failure (ARF) involves stimulation of tubular epithelial cell proliferation. The aim of this exploratory study was to evaluate the effects of preconditioning donor animals with rapamycin and tacrolimus to prevent ischaemia-reperfusion (I/R) injury. Twelve hours before nephrectomy, the donor animals received immunosuppressive drugs. The animals were divided into four groups, as follows: group 1 control: no treatment; group 2: rapamycin (2 mg/kg); group 3 FK506 (0, 3 mg/kg); and group 4: FK506 (0, 3 mg/kg) plus rapamycin (2 mg/kg). The left kidney was removed and after 3 h of cold ischaemia, the graft was transplanted. Twenty-four hours after transplant, the kidney was recovered for histological analysis and cytokine expression. Preconditioning treatment with rapamycin or tacrolimus significantly reduced blood urea nitrogen and creatinine compared with control [blood urea nitrogen (BUN): P < 0·001 versus control and creatinine: P < 0·001 versus control]. A further decrease was observed when rapamycin was combined with tacrolimus. Acute tubular necrosis was decreased significantly in donors treated with immunosuppressants compared with the control group (P < 0·001 versus control). Moreover, the number of apoptotic nuclei in the control group was higher compared with the treated groups (P < 0·001 versus control). Surprisingly, only rapamycin preconditioning treatment increased anti-apoptotic Bcl2 levels (P < 0·001). Finally, inflammatory cytokines, such as tumour necrosis factor (TNF)-α and interleukin (IL)-6, showed lower levels in the graft of those animals that had been pretreated with rapamycin or tacrolimus. This exploratory study demonstrates that preconditioning donor animals with rapamycin or tacrolimus improves clinical outcomes and reduce necrosis and apoptosis in kidney I/R injury.

Influence of the food to microorganisms (F/M) ratio and temperature on batch anaerobic digestion processes with and without zeolite addition

The main objective of this work was to evaluate the influence of the food to microorganisms (F/M) ratio and temperature on batch anaerobic digestion processes carried out with and without zeolite addition as a microbial carrier. Three laboratory-scale experimental runs were conducted using a synthetic substrate with a COD:N:P ratio of 500:5:1. The first run (I) was conducted at a constant temperature of 27°C, increasing the F/M ratio from 0.21 to 0.40 (g COD/g VSS). During the second run (II) the temperature and the F/M ratio increased from 27°C to 37°C and from 0.21 to 0.40, respectively. Finally, in the third experimental run (III) the F/M ratio achieved high values (1.92 and 1.30) either by varying the substrate concentration at a constant biomass concentration or by increasing the biomass concentration at a constant substrate concentration. Higher biomass growth rate, COD removal and methane production were found in the reactors with zeolite, especially at the highest F/M assayed during the first run. The highest ammonium removals were also achieved at the highest F/M ratio (0.40) in the reactors with zeolite. Within the range studied (25°C-37°C) in the reactors with zeolite operating at 37°C, the second run demonstrated the low influence of temperature on substrate consumption and ammonia removal, with 93% and 70% of COD and ammonia removal efficiencies, respectively. The third run corroborated the results previously obtained and fit the experimental results to simple kinetic models, the Monod model being the most adequate for predicting the behavior of the systems studied. The maximum specific microorganism growth rate (μ(max)) values for the reactors with zeolite were almost twice as high as those obtained for the reactors without zeolite for similar F/M ratios.

The predictive value of criteria for student admission to dentistry

INTRODUCTION

In this study, we investigated the value of an individual selection procedure to choose dental students for the Faculty of Dental Medicine at the University of Witten/Herdecke, Germany. The selection procedure was divided into the following four steps: step one consisted of a formal application; step two consisted of a practical test; step three consisted of a personal interview; and step four consisted of a final selection by an independent committee.

MATERIAL AND METHODS

Data from 196 students were collected from the university files. The following data were compared: the grades of the final secondary school certificate (Abiturnoten) were compared with the grades of the Natural Science Examination (naturwissenschaftliche Vorprüfung), first Dental Examination (zahnärztliche Vorprüfung) and State Board Examination (Staatsexamen); specialisation or non-specialisation at secondary school in natural sciences was compared with the grades of the Natural Science Examination and the first Dental Examination; the results of the practical test of the selection procedure were compared with the grades of the practical examination in the first Dental Examination; the interview recommendations to the committee were compared with the grades of the first Dental Examination and the State Board Examination.

RESULTS

The results showed a positive correlation (R = 0.34; P < 0.001) between the secondary school grades and the Natural Science Examination grades. The correlation was weaker between the grades of the first Dental Examination and State Board Examination. No correlation was found between the specialisation during secondary school in biology, chemistry and physics or non-specialisation, and the results of the Natural Science Examination and first Dental Examination. A weak correlation was found between the grades the candidates obtained in the practical test of the selection procedure and the first Dental Examination.

The use of Eugenol and electro-narcosis as anaesthetics: transcriptional impacts on the European eel (Anguilla anguilla L.)

Ecotoxicological studies aim to assess the potential environmental risks of various products. This implies the use of various biological models and tests on live animals. In case of handling fish and mammals, ethical rules have to be respected. The use of anaesthesia is considered to be the best way to ensure animal welfare. Eugenol and electro-narcosis are among the most popular chemical and physical anaesthetics used in fisheries and by field biologists. In this study, the genetic and endocrine impacts of these anaesthetics were assessed in order to establish whether the use of such methods could skew the results of ecotoxicological studies. Twenty yellow European eels (Anguilla anguilla) were submitted to Eugenol (50mg/L) and electro-narcosis until they reached a level of deep anaesthesia, while 20 other eels were kept aware. Five anaesthetized and five unanaesthetized eels were sacrificed and analysed directly after treatment and after 1, 7 and 21 days of recovery. At the brain level, Eugenol triggered an increase in the transcription level of genes encoding proteins involved in oxidative stress responses (catalase expression 2.5-fold, mitochondrial superoxide dismutase expression 3-fold), probably due to a hypoxic event during anaesthesia. Later impacts were detected in muscles 21 days after anaesthesia (ATP synthase subunit 6 3-fold, NADH deshydrogenase subunit 5 4-fold and mitochondrial superoxide dismutase 3-fold increased) revealing oxidative stress from an accrued mitochondrial respiratory metabolism. Hormone dosages showed that the use of Eugenol reduced the release of plasma cortisol during anaesthesia. However, this impact seemed to be reversible within one day. In case of electro-narcosis, no significant variation in transcriptional levels could be detected between anaesthetized and unanaesthetized eels. Our results suggest that the use of Eugenol as an aesthetic in ecotoxicological studies measuring gene expression or plasma cortisol concentration is not appropriate, while electro-narcosis does not seem to have any impact, at least on the parameters taken into consideration in this study.