The proteomics analysis reported here shows that a major cellular response to oxidative stress is the modification of several peroxiredoxins. An acidic form of the peroxiredoxins appeared to be systematically increased under oxidative stress conditions. Peroxiredoxins are enzymes catalyzing the destruction of peroxides. In doing so, a reactive cysteine in the peroxiredoxin active site is weakly oxidized (disulfide or sulfenic acid) by the destroyed peroxides. Cellular thiols (e.g. thioredoxin) are used to regenerate the peroxiredoxins to their active state. Tandem mass spectrometry was carried out to characterize the modified form of the protein produced in vivo by oxidative stress. The cysteine present in the active site was shown to be oxidized into cysteic acid, leading to an inactivated form of peroxiredoxin. This strongly suggested that peroxiredoxins behave as a dam upon oxidative stress, being both important peroxidedestroying enzymes and peroxide targets. Results obtained in a primary culture of Leydig cells challenged with tumor necrosis factor ␣ suggested that this oxidized/native balance of peroxiredoxin 2 may play an active role in resistance or susceptibility to tumor necrosis factor ␣-induced apoptosis.

The choroid plexus epithelium controls the movement of solutes between the blood and the cerebrospinal fluid. It has been considered as a functionally more immature interface during brain development than in adult. The anatomical basis of this barrier is the interepithelial choroidal junction whose tightness has been attributed to the presence of claudins. We used quantitative real-time polymerase chain reaction, Western blot and immunohistochemistry to identify different claudins in the choroid plexuses of developing and adult rats. Claudin-1, -2, and -3 were highly and selectively expressed in the choroid plexus as compared to brain or parenchyma microvessels and were localized at epithelial junctions. Claudin-6, -9, -19, and -22 also displayed a previously undescribed choroidal selectivity, while claudin-4, -5, and -16 were enriched in the cerebral microvessels. The choroidal pattern of tight junction protein expression in prenatal brains was already complex and included occludin and zonula occludens proteins. It differed from the adult pattern in that the pore-forming claudin-2, claudin-9, and claudin-22 increased during development, while claudin-3 and claudin-6 decreased. Claudin-2 and claudin-11 presented a mirror image of abundance between lateral ventricle and fourth ventricle choroid plexuses. Imunohistochemical analysis of human fetal and postnatal brains for claudin-1, -2, and -3 demonstrated their early presence and localization at the apico-lateral border of the choroid plexus epithelial cells. Overall, choroidal epithelial tight junctions are already complex in developing brain. The observed differences in claudin expression between developing and adult choroid plexuses may indicate developmental differences in selective blood–cerebrospinal fluid transport functions.Electronic supplementary materialThe online version of this article (doi:10.1007/s00418-012-1001-9) contains supplementary material, which is available to authorized users.

Although most pituitary tumors are benign, some are invasive or aggressive. In the absence of specific markers of malignancy, only tumors with metastases are considered malignant. To identify markers of invasion and aggressiveness, we focused on prolactin (PRL) tumors in the human and rat. Using radiology and histological methods, we classified 25 human PRL tumors into three groups (non-invasive, invasive, and aggressive-invasive) and compared them with a model of transplantable rat PRL tumors with benign and malignant lineages. Combining histological (mitoses and labeling for Ki-67, P53, pituitary transforming tumor gene (PTTG), and polysialic acid neural cell adhesion molecule) and transcriptomic (microarrays and q-RTPCR) methods with clinical data (post-surgical outcome with case-control statistical analysis), we found nine genes implicated in invasion (ADAMTS6, CRMP1, and DCAMKL3) proliferation (PTTG, ASK, CCNB1, AURKB, and CENPE), or pituitary differentiation (PITX1) showing differential expression in the three groups of tumors (PZ0.015 to 0.0001). A case-control analysis, comparing patients in remission (9 controls) and patients with persistent or recurrent tumors (14 cases) revealed that eight out of the nine genes were differentially up-or downregulated (PZ0.05 to 0.002), with only PTTG showing no correlation with clinical course (PZ0.258). These combined histological and transcriptomic analyses improve the pathological diagnosis of PRL tumors, indicating a reliable procedure for predicting tumor aggressiveness and recurrence potential. The similar gene profiles found between non-invasive human and benign rat tumors, as well as between aggressive-invasive human and malignant rat tumors provide new insights into malignancy in human pituitary tumors.

The retinal circadian clock is crucial for optimal regulation of retinal physiology and function, yet its cellular location in mammals is still controversial. We used laser microdissection to investigate the circadian profiles and phase relations of clock gene expression and Period gene induction by light in the isolated outer (rods/cones) and inner (inner nuclear and ganglion cell layers) regions in wild-type and melanopsin-knockout (Opn 4 (-/-) ) mouse retinas. In the wild-type mouse, all clock genes are rhythmically expressed in the photoreceptor layer but not in the inner retina. For clock genes that are rhythmic in both retinal compartments, the circadian profiles are out of phase. These results are consistent with the view that photoreceptors are a potential site of circadian rhythm generation. In mice lacking melanopsin, we found an unexpected loss of clock gene rhythms and of the photic induction of Per1-Per2 mRNAs only in the outer retina. Since melanopsin ganglion cells are known to provide a feed-back signalling pathway for photic information to dopaminergic cells, we further examined dopamine (DA) synthesis in Opn 4 (-/-) mice. The lack of melanopsin prevented the light-dependent increase of tyrosine hydroxylase (TH) mRNA and of DA and, in constant darkness, led to comparatively high levels of both components. These results suggest that melanopsin is required for molecular clock function and DA regulation in the retina, and that Period gene induction by light is mediated by a melanopsin-dependent, DA-driven signal acting on retinal photoreceptors.

BackgroundHantaviruses are single-stranded RNA viruses, which are transmitted to humans primarily via inhalation of aerosolised virus in contaminated rodent urine and faeces. Whilst infected reservoir hosts are asymptomatic, human infections can lead to two clinical manifestations, haemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS), with varying degrees of clinical severity. The incidence of rodent and human cases of Seoul virus (SEOV) in Europe has been considered to be low, and speculated to be driven by the sporadic introduction of infected brown rats (Rattus norvegicus) via ports.MethodsBetween October 2010 and March 2012, 128 brown rats were caught at sites across the Lyon region in France.ResultsSEOV RNA was detected in the lungs of 14% (95% CI 8.01 – 20.11) of brown rats tested using a nested pan-hantavirus RT-PCR (polymerase gene). Phylogenetic analysis supports the inclusion of the Lyon SEOV within Lineage 7 with SEOV strains originating from SE Asia and the previously reported French & Belgian SEOV strains. Sequence data obtained from the recent human SEOV case (Replonges) was most similar to that obtained from one brown rat trapped in a public park in Lyon city centre. We obtained significantly improved recovery of virus genome sequence directly from SEOV infected lung material using a simple viral enrichment approach and NGS technology.ConclusionsThe detection of SEOV in two wild caught brown rats in the UK and the multiple detection of SEOV infected brown rats in the Lyon region of France, suggests that SEOV is circulating in European brown rats. Under-reporting and difficulties in identifying the hantaviruses associated with HFRS may mask the public health impact of SEOV in Europe.

Nauplii of Calanus helgolandicus were raised from eggs, laid within a 12 h period, to Copepodite Stage I (CI) on 5 different species of algae at high concentrations at 15°C. The diets used were Isochrysis galbana (5 µm spherical diameter), Rhodomonas baltica (7 µm), the coccolithophorid Pleurochrysis carterae (12 µm), the diatom Thalassiosira weissflogii (14 µm) and the dinoflagellate Prorocentrum micans (30 µm). Each day a sample was taken and preserved for later cohort analysis. Growth was estimated from CHN samples collected almost daily, from which naupliar stages were also distinguished. Ingestion was measured for each naupliar feeding stage. The fastest development was obtained with I. galbana and P. micans. We found the highest value of carbon and nitrogen content of Naupliar Stages NV to CI for individuals reared on the smallest algae, I. galbana and R. baltica. However, ingestion rate in terms of carbon or nitrogen was lowest with these same (smallest) algae. Therefore, the gross growth efficiency was highest for the smallest algae. These results suggest the following: Firstly, that factors influencing development time and weight in stage are different; weight in stage is negatively related to algal size, whereas development time is independent of it. The quality of the algal biochemical components could be the factor influencing development. Secondly, that small algae are fully assimilated in the gut whereas larger cells, i.e. those with indigestible components around the cell (theca, frustule, calcium layer) are only partly assimilated.KEY WORDS: Calanus helgolandicus · Nauplii · Growth · Development · Ingestion · Efficiency · Food quality Resale or republication not permitted without written consent of the publisherMar Ecol Prog Ser 216: [151][152][153][154][155][156][157][158][159][160][161][162][163][164][165] 2001 Some studies have found consumption of diatoms by females to result in low hatching success (Ianora & Poulet 1993, Poulet et al. 1994, Chaudron et al. 1996, Ban et al. 1997), but this is still open to discussion (Jónasdóttir & Kiørboe 1996, Jónas-dóttir et al. 1998, Irigoien et al. 2000b.Development, body size and weight of nauplii and copepodites have been negatively related to temperature (Thompson 1982, Peterson 1986, Hopcroft & Roff 1998. Ontogenetic differences in the physiological response to temperature in copepods have also been noted (Pedersen & Tande 1992). The effect of food quantity on growth processes has often been unclear (Hart 1990, Hopcroft & Roff 1998, but some studies have clearly established an effect of food limitation on wild nauplii (Lopez 1991, Melle 1998, and this has been further substantiated by laboratory studies (Green et al. 1991, Lopez 1996.Food quality is another factor which has to be considered when examining variability in naupliar growth (Mullin & Brooks 1970, Paffenhöfer 1971, 1976, Fernández 1979a,b, Diel & Klein Breteler 1986, Verity & Smayda 1989. The major algal characteristics of importance are biochemical content, morphology, and di...

Integrative genomics approaches associating DNA structure and transcriptomic analysis should allow the identification of cascades of events relating to tumor aggressiveness. While different genome alterations have been identified in pituitary tumors, none have ever been correlated with the aggressiveness. This study focused on one subtype of pituitary tumor, the prolactin (PRL) pituitary tumors, to identify molecular events associated with the aggressive and malignant phenotypes. We combined a comparative genomic hybridization and transcriptomic analysis of 13 PRL tumors classified as nonaggressive or aggressive. Allelic loss within the p arm region of chromosome 11 was detected in five of the aggressive tumors. Allelic loss in the 11q arm was observed in three of these five tumors, all three of which were considered as malignant based on the occurrence of metastases. Comparison of genomic and transcriptomic data showed that allelic loss impacted upon the expression of genes located in the imbalanced region. Data filtering allowed us to highlight five deregulated genes (DGKZ, CD44, TSG101, GTF2H1, HTATIP2), within the missing 11p region, potentially responsible for triggering the aggressive and malignant phenotypes of PRL tumors. Our combined genomic and transcriptomic analysis underlines the importance of chromosome allelic loss in determining the aggressiveness and malignancy of tumors.

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