m5C Methylation Guides Systemic Transport of Messenger RNA over Graft Junctions in Plants

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Suicides among cancer patients in Lithuania: A population-based census-linked study

Background: This study aims to estimate suicide risk and its socio-demographic determinants among cancer patients in the country showing the highest suicide rates among developed countries. Methods: The study is based on a unique census-linked dataset based on the linkages between the records from death and cancer registers and the 2001 population census records. Standardized mortality ratios for suicide (SMRs) were calculated for patients diagnosed with cancer in Lithuania between April 6, 2001 and December 31, 2009, relative to suicide rates in the general population. Results: We found that the relative suicide risk was elevated for both males and females, with SMRs of 1.43 (95% CI 1.23–1.66) and 1.32 (95% CI 0.95–1.80), respectively. This relationship for females became statistically significant and stronger after excluding skin cancers. The highest suicide risks were observed at older ages and during the period shortly after the diagnosis. The groups showing an increased suicide risk include lower educated, non-married, and rural male patients. Conclusion: The results of our study point to inadequacies of the health care system in dealing with mental health problems of cancer patients. Interventions allowing early detection of depression or suicidal ideation may help to prevent suicide among cancer patients in Lithuania.     

Dynamic Co-evolution of Peptides and Chemical Energetics, a Gateway to the Emergence of Homochirality and the Catalytic Activity of Peptides

We propose a scenario for the dynamic co-evolution of peptides and energy on the primitive Earth. From a multi component system consisting of hydrogen cyanide, several carbonyl compounds, ammonia, alkyl amine, carbonic anhydride, borate and isocyanic acid, we show that the reversibility of this system leads to several intermediate nitriles, that irreversibly evolve to alpha-amino acids and N-carbamoyl amino acids via selective catalytic processes. On the primitive Earth these N-carbamoyl amino acids combined with energetic molecules (NOx) may have been the core of a molecular engine producing peptides permanently and assuring their recycling and evolution. We present this molecular engine, a production example, and its various selectivities. The perspectives for such a dynamic approach to the emergence of peptides are evoked in the conclusion.     

Locomotor activity rhythms in two sympatric parasitoid insects: Eupelmus orientalis and Eupelmus vuilleti (Hyménoptera, Eupelmidae)

With an automatic image analysis device, we studied the temporal distribution of the locomotor activity of E. orientalis and E. vuilleti during 24 h, and over several days to know whether the activity rhythms of these two Eupelmidae play a role in their competitive interactions. The analysis of locomotor activity rhythms of E. orientalis and E. vuilleti shows that the locomotor activity of both species presents daily cyclic variations. These two Eupelmidae have similar activity rhythms. Displacements of these parasitoids essentially take place during the photophase. But the activity of E. vuilleti is earlier, because the individuals of this species start their activity on average 4 to 5 h earlier than those of E. orientalis. E. vuilleti begins its displacements several hours before the onset of lighting, whereas E. orientalis is active only in the presence of the light. This shift of starting activity is thus a factor allowing these concurrent species to minimize their interactions during the cohabitation period in traditional granaries after the harvests of cowpea.     

Intimate Rendezvous in a Tritrophic Context? Nothing but the Girls for Male Lysiphlebus testaceipes

In insects, mating often occurs after natal dispersal, and hence relies on a coevolved combination of sexual communication and movement allowing mate encounter. Volatile sex pheromones are widespread, generally emitted by females and triggering in‐flight orientation of conspecific males. In parasitoid wasps, unmated females can start laying unfertilized eggs via parthenogenesis so that host patches could serve as sites of rendezvous for mating. Males could therefore use cues associated with host patches to focus their search on females that have successfully found oviposition sites. We hypothesized that in parasitoids exploiting herbivorous hosts, sex pheromones, and herbivore‐induced plant volatiles (HIPV) should act in synergy, triggering male orientation toward ovipositing females. We tested this hypothesis with the aphid parasitoid Lysiphlebus testaceipes. Results from both field and laboratory experiments show that males are strongly attracted to virgin females, but that volatiles from aphid‐infested plants have no effect on male orientation, neither has a cue, nor in interaction with the female sex pheromone. The absence of synergy between sex pheromones and HIPV contrasts with results on other species and raises interesting questions on mating systems and sexual selection in parasitoid wasps.     

Gonad Differentiation in the Rabbit: Evidence of Species-Specific Features

The rabbit is an attractive species for the study of gonad differentiation because of its 31-day long gestation, the timing of female meiosis around birth and the 15-day delay between gonadal switch and the onset of meiosis in the female. The expression of a series of genes was thus determined by qPCR during foetal life until adulthood, completed by a histological analysis and whenever possible by an immunohistological one. Interesting gene expression profiles were recorded. Firstly, the peak of SRY gene expression that is observed in early differentiated XY gonads in numerous mammals was also seen in the rabbit, but this expression was maintained at a high level until the end of puberty. Secondly, a peak of aromatase gene expression was observed at two-thirds of the gestation in XX gonads as in many other species except in the mouse. Thirdly, the expression of STRA8 and DMC1 genes (which are known to be specifically expressed in germ cells during meiosis) was enhanced in XX gonads around birth but also slightly and significantly in XY gonads at the same time, even though no meiosis occurs in XY gonad at this stage. This was probably a consequence of the synchronous strong NANOS2 gene expression in XY gonad. In conclusion, our data highlighted some rabbit-specific findings with respect to the gonad differentiation process.     

Rapid SERS monitoring of lipid‐peroxidation‐derived protein modifications in cells using photonic crystal fiber sensor

We proposed a side channel photonic crystal fiber (SC‐PCF) based Surface enhanced Raman spectroscopy (SERS) platform which is able to accurately monitor lipid peroxidation derived protein modifications in cells. This platform incorporates linoleamide alkyne (LAA), which is oxidized and subsequently modifies proteins in cells with alkyne functional group upon lipid peroxidation. By loading the side channel of SC‐PCF with a mixture of gold nanoparticles and LAA treated cells, and subsequently measuring the interference‐free alkyne Raman peak from these proteins in cells, strong SERS signal was obtained. The platform provides a method for the rapid monitoring of lipid peroxidation derived protein modification in cells.

     

Hydrocarbons,sterols and tocopherols in the seeds of six Adansonia species

The composition of the unsaponifiable matter of the lipids of six Adansonia species (A. grandidieri, A. za, A. fony, A. madagascariensis, A. digitata and A. suarezensis) was investigated. The total unsaponifiable content, its general composition and the identity of the components of the hydrocarbon, sterol and tocopherol fractions are presented. The unsaponifiable content in oil ranges from 0.4 to 1.1% (hexane method) and from 0.6 to 2.2% (diethyl ether method). In two species (A. grandidieri and A. suarezensis) the major components are 4-demethylsterols (23–42%) tocopherols (37-10%) and hydrocarbons (15–17%). In both species examined, eight 4-demethylsterols occur in the sterol fraction with sitosterol (81–88%) being predominant. Among the four tocopherols present, γ-tocopherol (68–98%) is the major compound. Each Adansonia species shows a characteristic gas liquid chromatography pattern for the hydrocarbon fraction. Squalene is the major component for five species (40–75%). Iso-, anteiso- and other branched hydrocarbons were not identified but were present in small amounts in comparison with n-alkanes. The dominance of odd- over even-carbon number chain length of n-alkanes was not observed in any species. The results show that C₂₂, C₂₅, C₂₆, C₂₇, C₂₈ and C₂₉ are the most frequent major constituents.