Whole-Exome Sequencing in the Isolated Populations of Cilento from South Italy.

The present study describes the genetic architecture of the isolated populations of Cilento, through the analysis of exome sequence data of 245 representative individuals of these populations. By annotating the exome variants and cataloguing them according to their frequency and functional effects, we identified 347,684 variants, 67.4% of which are rare and low frequency variants, and 1% of them (corresponding to 319 variants per person) are classified as high functional impact variants; also, 39,946 (11.5% of the total) are novel variants, for which we determined a significant enrichment for deleterious effects. By comparing the allele frequencies in Cilento with those from the Tuscan population from the 1000 Genomes Project Phase 3, we highlighted an increase in allele frequency in Cilento especially for variants which map to genes involved in extracellular matrix formation and organization. Furthermore, among the variants showing increased frequency we identified several known rare disease-causing variants. By different population genetics analyses, we corroborated the status of the Cilento populations as genetic isolates. Finally, we showed that exome data of Cilento represents a useful local reference panel capable of improving the accuracy of genetic imputation, thus adding power to genetic studies of human traits in these populations.

Beyond the grave: When is cell death critical for immunity to infection?

Immune cell death is often observed in response to infection. There are three potential beneficial outcomes after host cell death: (1) the removal of an intracellular niche for microbes, (2) direct microbicidal activity of released components and (3) the propagation of an inflammatory response. Recent findings suggest that three forms of non-apoptotic regulated cell death, pyroptosis, necroptosis and NETosis, can impact on immunity to bacterial infection. However, it is challenging to design experiments that unequivocally prove the advantageous effects of regulated cell death on immunity. Recent advances in the genetic manipulation of regulated cell death and danger-associated molecular patterns and 'alarmins', such as HMGB1 and the IL-1 family, may hold the key to delineating the consequences of cell death in immunity to infection.

Growth response of soda lake bacterial communities to simulated rainfall.

Moderately saline soda lakes harbor extremely abundant and fast growing bacterial communities. An interesting phenomenon of an explosive bacterial growth in shallow soda lakes in Eastern Austria after dilution with rainwater, concomitantly with a significant decrease in temperature was observed in a former study. In the present study, we tried to identify the factors being responsible for this enhanced bacterial growth in laboratory batch cultures. Three experiments were performed with water taken from two different lakes at different seasons. Natural soda lake water was diluted with distilled water, artificial lake water, sterile filtered soda lake water, and grazer-free water to test (1) for the influence of compatible solutes released to the environment and reduced salt stress after osmotic down-shock, (2) for the influence of nutrients, which may be washed in from the dry areas of the lake bottom after rainfall and (3) for the decrease of grazing pressure due to dilution. The potential influence of (4) viruses was indirectly deduced. The response of the bacterial community to the manipulations was measured by changes in bacterial numbers, the incorporation of (3)H-leucine and the concomitant determination of the amount of (3)H-leucine uptaking bacteria by microautoradiography. The influence of the environmental factors enhancing bacterial growth after a simulated rainfall event showed variations between the lakes and over the seasons. The addition of nutrients was, in all experiments, the main factor triggering bacterial growth. The decrease in grazing pressure and viral lysis after dilution was of significant importance in two of three experiments. In the experiment with the highest salinity, we could show that either compatible solutes released after osmotic down-shock and used as a source of nutrients for the soda lake bacterial populations or reduced salt stress were most probably responsible for the observed marked enhancement of bacterial growth.

Dynamics and predicted decline of Anguillicola crassus infection in European eels, Anguilla anguilla, in Neusiedler See, Austria.

The eel population in Neusiedler See has been maintained by regular massive stocking since 1958. After the establishment of the National Park Neusiedler See-Seewinkel in 1993, eel stocking was prohibited and the population, together with the specific parasites of eels, was predicted to decline to extinction within 10 years. This investigation was undertaken to document the decline and extinction of the Anguillicola crassus population in eels. From 1994 to 2001, 720 eels were collected from two sites in the lake. Prevalence and abundance of A. crassus were lower in spring than in summer and autumn and larger eels harboured more parasites than smaller ones. Neither year of study nor sampling site were correlated with parasite infection levels. No significant trend in the population parameters of A. crassus was detected over the 8 years of the survey. This suggested that there had been no significant decline in the eel population. This suggestion was confirmed by investigations of the fishery, which also found evidence of regular illegal stocking. The stability of the A. crassus population over the past decade seems to reflect the lack of change in eel population density. No mass mortalities of eels occurred over the period despite the many similarities between Neusiedler See and Lake Balaton in Hungary. Differences in eel size, eel diet and the lack of large-scale insecticide use are discussed as possible explanations for the absence of eel mass mortalities in Neusiedler See.

Long-term investigation of the composition and richness of intestinal helminth communities in the stocked population of eel, Anguilla anguilla, in Neusiedler See, Austria.

Data from a long-term study of the intestinal helminth parasite community of eels, Anguilla anguilla, stocked into the shallow eutrophic Neusiedler See, Austria, were collected over an 8 year period (1994-2001). In total, 720 eels from 2 sampling sites were examined. The parasite community showed characteristics similar to those in the natural eel populations in rivers of the UK and mainland Europe: it was species poor, with only 5 species (Acanthocephalus lucii, Acanthocephalus anguillae, Raphidascaris acus, Proteocephalus macrocephalus, Bothriocephalus claviceps) comprising the component community and a maximum infracommunity richness of 4 species. Over the period, the intestinal parasite community of the sampling site in Illmitz, which was originally dominated by A. lucii, changed. As levels of A. anguillae increased to a point at which it dominated the community, diversity increased whilst dominance of a single species decreased. By contrast the community in the southern sampling site remained rather constant with a continuous high infection level of A. anguillae and low abundance of A. lucii. Both acanthocephalan species exhibited higher infection levels in larger eels and in different seasons of the year and the infection parameters were significantly different between the years of study. The significant differences in the infection levels of the 2 acanthocephalan species at the 2 sampling sites were surprising as both acanthocephalan species use the same intermediate host, Asellus aquaticus, and the sampling sites were in close proximity and were similar in terms of water quality, host size and invertebrate abundance. Differences in the fish communities of the 2 sampling sites and eel movements rather than interspecific competition are discussed as possible explanations for the differences in the parasite communities of the 2 sampling sites.

Factors controlling extremely productive heterotrophic bacterial communities in shallow soda pools.

Dilute soda lakes are among the world's most productive environments and are usually dominated by dense blooms of cyanobacteria. Up to now, there has been little information available on heterotrophic bacterial abundance, production, and their controlling factors in these ecosystems. In the present study the main environmental factors responsible for the control of the heterotrophic bacterial community in five shallow soda pools in Eastern Austria were investigated during an annual cycle. Extremely high cyanobacterial numbers and heterotrophic bacterial numbers up to 307 x 10(9) L(-1) and 268 x 10(9) L(-1) were found, respectively. Bacterial secondary production rates up to 738 micro g C L(-1) h(-1) and specific growth rates up to 1.65 h(-1) were recorded in summer and represent the highest reported values for natural aquatic ecosystems. The combination of dense phytoplankton blooms, high temperature, high turbidity, and nutrient concentration due to evaporation is supposed to enable the development of such extremely productive microbial populations. By principal component analysis containing the data set of all five investigated pools, two factors were extracted which explained 62.5% of the total variation of the systems. The first factor could be interpreted as a turbidity factor; the second was assigned to as concentration factor. From this it was deduced that bacterial and cyanobacterial abundance were mainly controlled by wind-induced sediment resuspension and turbidity stabilized by the high pH and salinity and less by evaporative concentration of salinity and dissolved organic carbon. Bacterial production was clustered with temperature in factor 3, showing that bacterial growth was mainly controlled by temperature. The concept of describing the turbid water columns of the shallow soda pools as "fluid sediment" is discussed.

Extremely productive microbial communities in shallow saline pools respond immediately to changing meteorological conditions.

Diel changes in bacterial and cyanobacterial numbers, as well as heterotrophic bacterial production, were examined in two shallow alkaline pools, harbouring dense populations of cyanobacteria (up to 1100 x 109 cells l-1) and bacteria (up to 500 x 109 cells l-1). Together with the recorded bacterial production rates (925 micro gC l-1x h-1), these values are the highest reported for natural aquatic ecosystems. The investigations were performed during a fair-weather situation, and during a rapid change after a long-term fair-weather situation to thunderstorms and heavy rainfall. During fair weather, bacterial growth was significantly correlated to the diurnal light and temperature cycle. Prokaryotic abundances were fairly constant, and loss by grazing and viral lysis must have been of significant importance. During the invasion of rainy weather, the prokaryotic community showed a strong and immediate response. A significant enhancement of bacterial growth followed after rainfall, suggesting that the high salt concentrations had inhibited bacterial activity. Changes in bacterial and cyanobacterial numbers were consistent with this pattern. From comparison with the available literature, we conclude that diel changes of bacterioplankton are regulated by a complex combination of environmental factors specific for each investigated ecosystem. In the soda pools investigated, external abiotic factors were dominant on a diel scale. In larger ecosystems, such factors are much more buffered and internal biotic interactions may prevail.

Drosophila separase is required for sister chromatid separation and binds to PIM and THR.

Drosophila PIM and THR are required for sister chromatid separation in mitosis and associate in vivo. Neither of these two proteins shares significant sequence similarity with known proteins. However, PIM has functional similarities with securin proteins. Like securin, PIM is degraded at the metaphase-to-anaphase transition and this degradation is required for sister chromatid separation. Securin binds and inhibits separase, a conserved cysteine endoprotease. Proteolysis of securin at the metaphase-to-anaphase transition activates separase, which degrades a conserved cohesin subunit, thereby allowing sister chromatid separation. To address whether PIM regulates separase activity or functions with THR in a distinct pathway, we have characterized a Drosophila separase homolog (SSE). SSE is an unusual member of the separase family. SSE is only about one-third the size of other separases and has a diverged endoprotease domain. However, our genetic analyses show that SSE is essential and required for sister chromatid separation during mitosis. Moreover, we show that SSE associates with both PIM and THR. Although our work shows that separase is required for sister chromatid separation in higher eukaryotes, in addition, it also indicates that the regulatory proteins have diverged to a surprising degree, particularly in Drosophila.

Degradation of Drosophila PIM regulates sister chromatid separation during mitosis.

Drosophila Pimples (PIM) and Three rows (THR) are required for sister chromatid separation in mitosis. PIM accumulates during interphase and is degraded rapidly during mitosis. This degradation is dependent on a destruction box similar to that of B-type cyclins. Nondegradable PIM with a mutant destruction box can rescue sister chromatid separation in pim mutants but only when expressed at low levels. Higher levels of nondegradable PIM, as well as overexpression of wild-type PIM, inhibit sister chromatid separation. Moreover, cells arrested in mitosis before sister chromatid separation (by colcemid or by mutations in fizzy/CDC20) fail to degrade PIM. Thus, although not related by primary sequence, PIM has intriguing functional similarities to the securin proteins of budding yeast, fission yeast, and vertebrates. Whereas these securins are known to form a complex with separins, we show that PIM associates in vivo with THR, which does not contain the conserved separin domain.

A screen for modifiers of cyclin E function in Drosophila melanogaster identifies Cdk2 mutations, revealing the insignificance of putative phosphorylation sites in Cdk2.

In higher eukaryotes, cyclin E is thought to control the progression from G1 into S phase of the cell cycle by associating as a regulatory subunit with cdk2. To identify genes interacting with cyclin E, we have screened in Drosophila melanogaster for mutations that act as dominant modifiers of an eye phenotype caused by a Sevenless-CycE transgene that directs ectopic Cyclin E expression in postmitotic cells of eye imaginal disc and causes a rough eye phenotype in adult flies. The majority of the EMS-induced mutations that we have identified fall into four complementation groups corresponding to the genes split ends, dacapo, dE2F1, and Cdk2(Cdc2c). The Cdk2 mutations in combination with mutant Cdk2 transgenes have allowed us to address the regulatory significance of potential phosphorylation sites in Cdk2 (Thr 18 and Tyr 19). The corresponding sites in the closely related Cdk1 (Thr 14 and Tyr 15) are of crucial importance for regulation of the G2/M transition by myt1 and wee1 kinases and cdc25 phosphatases. In contrast, our results demonstrate that the equivalent sites in Cdk2 play no essential role.

Continuous Cyclin E expression inhibits progression through endoreduplication cycles in Drosophila.

Entry into S phase of the mitotic cell cycle is normally strictly dependent on progression through the preceding M phase. In contrast, during endoreduplication, which accompanies post-mitotic cell growth in many organisms, repeated S phases occur without intervening M phases. Upon transition from mitotic to endoreduplication cycles in Drosophila embryos, expression of the mitotic cyclins A, B and B3 is terminated and Cyclin E expression is changed from a continuous into a periodic mode [1-3]. Here, we address whether these changes in cyclin expression are required for endoreduplication by continuously expressing Cyclin A, B, B3 or E in the salivary glands of Drosophila throughout late embryonic and larval development. With the exception of Cyclin A, expression of which inhibited endoreduplication effectively but only in a few, apparently randomly distributed, cells of the salivary gland, mitotic cyclin expression was found to have no effect. In contrast, Cyclin E expression resulted in a striking inhibition of endoreduplication and growth, preceded initially by an ectopic S phase occurring just after the onset of ectopic Cyclin E expression. This observation is consistent with our previous findings that Cyclin E is required, and pulses of ectopic expression are sufficient, for triggering endoreduplication S phases [4]. Our results indicate that Cyclin E activity, which triggers DNA replication, needs to be down-regulated to allow a subsequent S phase in vivo.

Quantifying the effects of distance and conspecifics on colonization: experiments and models using the loosestrife leaf beetle, Galerucella calmariensis.

The ability of an insect to disperse to new habitat patches is difficult to quantify, but key to the establishment and persistence of populations. In this study, we examined dispersal of the phytophagous chrysomelid beetle, Galerucella calmariensis, which is currently being introduced into North America for the biological control of purple loosestrife (Lythrum salicaria), an aggressive wetland weed. We used a mark, release, and recapture approach to determine how rates of colonization of host patches by this beetle are influenced by the distance of the patch from the source of dispersers, and by the presence of conspecifics at the patch. We released color-coded beetles at six distances from a long, linear patch of purple loosestrife that was divided into segments with and without conspecifics. We observed initial flight directions as beetles left the release points and collected all beetles that settled at the target patch. We found a bias in initial flight toward the target for distances up to 50 m. Over the 7 days of the experiment, beetles arrived at the target from all release points, including the farthest release point, 847 m away. G. calmariensis was strongly attracted to conspecifics when settling after dispersal; 86% of the 582 recovered beetles came from the segments inhabited by conspecifics. The probability of an individual arriving at the patch declined steeply with release distance. This relationship fits a model in which beetles move in a random direction and stop if they intercept the target patch, and where beetles are lost at a constant rate with distance travelled. The dispersal and patch-colonizing behavior of G. calmariensis is likely to have important consequences for the biological control program against purple loosestrife.

41-month follow-up of risk factors correlated with new coronary events in 708 elderly patients.

A prospective study correlated coronary risk factors with new coronary events in 192 elderly men and 516 elderly women, mean age 82 +/- 8 years. Follow-up was 41 +/- 6 months (range 24-44). Coronary events (myocardial infarction, primary ventricular fibrillation, and sudden cardiac death) occurred in 64 of 192 men (33%) and in 149 of 516 women (29%), P not significant. Using univariate analysis, significant risk factors for coronary events were antecedent coronary artery disease, cigarette smoking, hypertension, diabetes mellitus, serum total cholesterol (TC) greater than or equal to 200 mg/dL and greater than or equal to 250 mg/dL, serum high-density lipoprotein cholesterol (HDL-C) less than 35 mg/dL, and serum TC/HDL-C greater than or equal to 6.5 in men and women, and obesity in women. Using multivariate analysis, significant risk factors for coronary events were age, antecedent coronary artery disease, cigarette smoking, hypertension, diabetes mellitus, and serum TC in men and women and serum HDL-C and serum triglycerides in women. Using univariate analysis, significant risk factors for coronary events in men and women with antecedent coronary artery disease were cigarette smoking, diabetes mellitus, serum TC greater than or equal to 250 mg/dL, and serum TC/HDL-C greater than or equal to 6.5. Using multivariate analysis, significant risk factors for coronary events in men and women with antecedent coronary artery disease were age, cigarette smoking, diabetes mellitus, serum TC, serum HDL-C, and serum triglycerides.(ABSTRACT TRUNCATED AT 250 WORDS)

[Physical examination preceding entry into apprenticeship: preventive measure or administrative burden?]. / L'examen médical précédant l'entrée en apprentissage: instrument de prévention ou tracasserie administrative?

The new Swiss federal legislation on vocational and trade training requires that all cantons organize a system of medical screening for young people entering an apprenticeship. This paper focuses on the principles and implementation of such an examination. It outlines the most frequent health problems young people may face upon leaving school and entering apprenticeship. It underlines the difficulties of this kind of examination, since absolute contra-indications to distinct professions are very rare. Indeed, the medical examination should not be a selection procedure but much more an occasion to facilitate the transition from school to workplace. With this objective, the canton of Vaud health authority has created an examination sheet that will be supplied each year to the physicians (private pediatricians, general practitioners and internists) examining about 5000 candidates. This instrument introduces a uniform history taking procedure oriented towards occupational medicine and focuses on a few important screening items. No laboratory tests are mandatory. The process does not use a contra-indication list, which most of the time appears fallacious. It insists on the importance of an assessment of each individual situation.