DNA methylation is generally limited to CpG doublets located at the gene promoter with an involvement in gene silencing. Surprisingly, two recent papers showed an extensive methylation affecting ...coding portions of transcriptionally active genes in human and plants prompting a rethink of DNA methylation in eukaryotes. Actually, gene body methylation is not surprising since it has been repeatedly reported in invertebrates, where it interferes with transcriptional elongation preventing aberrant transcription initiations. As a whole, the published data suggest that the most ancestral function of DNA methylation is the control of genes that are susceptible to transcriptional interference and not to gene silencing. The recruitment of DNA methylation for silencing represents a successive tinkered use. In view of this additional function, the invertebrate-vertebrate transition has been accompanied by new constraints on DNA methylation that resulted in the strong conservation of the DNA methylation machinery in vertebrates and in the non-viability of mutants lacking DNA methylation.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UL, UM, UPUK, VKSCE, ZAGLJ
The leafhopper Scaphoideus titanus is able to transmit 16SrV phytoplasmas agents of grapevine's flavescence dorée (FD) within 30–45 days, following an acquisition access period (AAP) of a few days ...feeding on infected plants as a nymph, a latency period (LP) of 3–5 weeks becoming meanwhile an adult, and an inoculation access period (IAP) of a few days on healthy plants. However, several aspects of FD epidemiology suggest how the whole transmission process may take less time, and may start directly with adults of the insect vector. Transmission experiments have been set up under lab condition. Phytoplasma‐free S. titanus adults were placed on broad bean (BB) plants (Vicia faba) infected by FD‐C (16SrV‐C) phytoplasmas for an AAP = 7 days. Afterwards, they were immediately moved onto healthy BB for IAP, which were changed every 7 days, obtaining three timings of inoculation: IAP 1, IAP 2 and IAP 3, lasting 7, 14 and 21 days from the end of AAP, respectively. DNA was extracted from plants and insects, and PCR tests were performed to identify FD phytoplasmas. Insects were dissected and fluorescence in situ hybridisation was made to detect the presence of phytoplasmas in midguts and salivary glands. The rate of infection in insects ranged 46–68% without significant differences among IAPs. Inoculation in plants succeeded in all IAPs, at a rate of 16–23% (no significant differences). Phytoplasma load was significantly higher in IAP 3 than IAP 1–2 for both plants and insects. Phytoplasmas were identified both in midgut and salivary glands of S. titanus at all IAP times. The possible implications of these results in the epidemiology of flavescence dorée are discussed.
The phytoplasmal agent of Flavescence dorée (FD) is transmitted to grapevine by the leafhopper Scaphoideus titanus. Even though 30‐45 days are reported to be required from acquisition (by nymphs) to inoculation (by adults), successful transmission could be achieved even after a shorter period, and it could start directly from adults. FD phytoplasma transmission experiments with S. titanus adults revealed that as soon as 14 days from acquisition the leafhoppers were able to transmit the pathogen to healthy broad beans. The results of this work open to new epidemiologic scenarios, which should be taken into account for FD management.
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BFBNIB, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
An emerging central concept in evolutionary biology suggests that symbiosis is a universal characteristic of living organisms that can help in understanding complex traits and phenotypes. During ...evolution, an integrative circuitry fundamental for survival has been established between commensal gut microbiota and host. On the basis of recent knowledge in worms, flies, and humans, an important role of the gut microbiota in aging and longevity is emerging. The complex bacterial community that populates the gut and that represents an evolutionary adapted ecosystem correlated with nutrition appears to limit the accumulation of pathobionts and infections in all taxa, being able of affecting the efficiency of the host immune system and exerting systemic metabolic effects. There is an urgent need to disentangle the underpinning molecular mechanisms, which could shed light on the basic mechanisms of aging in an ecological perspective. Thus, it appears possible to extend healthy aging and lifespan by targeting the host as a metaorganism by manipulating the complex symbiotic ecosystem of gut microbiota, as well as other possible ecosystems of the body.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, ODKLJ, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Heat-shock proteins 90 (hsp90s) are a class of molecules able to stabilize a network of 'client' proteins that are involved in several processes. Furthermore, recent studies indicated that mutations ...in the hsp90-encoding gene induce a wide range of phenotypic abnormalities, which have been interpreted as an increased sensitivity of different developmental pathways to hidden/cryptic mutations. In order to verify the role of hsp90 in aphids, we amplified and sequenced the hsp90 gene in 17 lineages of the peach potato aphid Myzus persicae (Sulzer, 1776) looking for the presence of mutations. In particular, we compared lineages with different reproductive modes (obligate vs. cyclical parthenogenesis), propensity to develop winged females and karyotype stability. Differently from the cyclical parthenogenetic lineages that possessed functional hsp90 genes, the seven analysed asexual lineages showed severe mutations (including frameshift and non-sense mutations). In vivo functional assays with the hsp90-inhibitor geldanamycin showed that some lineages with cyclical parthenogenesis may lose their ability to induce sexuales in the absence of active hsp90 revealing the presence of cryptic mutations in their genomes. As a whole, our data suggest that hsp90 could play in aphids a role in buffering hidden/cryptic mutations that disrupt cyclical parthenogenesis.
Aim
Laparoscopy offers the benefits of minimally invasive surgery and faster recovery. Acute surgical patients may potentially benefit from the great advantages of emergency laparoscopy, which is ...more clinically relevant in acute than elective patients. Fashioning a laparoscopic intracorporeal anastomosis (ICA) after emergent colorectal resection, whenever technically feasible and not contraindicated by the patient's general and haemodynamic condition, is a most challenging technical skill.
Method
During the period 2010–2016, 59 patients underwent a laparoscopic procedure for colorectal emergency in an acute care setting by a single operating surgeon with advanced laparoscopic skills and specific expertise in both colorectal surgery and acute care surgery. This series includes 32 laparoscopic right colectomies (12 for obstruction and 20 for perforation/peritonitis) and 27 left colectomies (6 for obstruction and 21 for perforation/peritonitis). Twenty‐eight ileocolic side‐to‐side ICA, and 27 left colonic ICA (3 colocolic, 24 colorectal) were performed.
Results
Reasonably good postoperative outcomes were observed in the entire series of 59 laparoscopic colectomies performed in an urgent setting. Overall, the major morbidity rate in the entire group was 16.9% (10/59) with an incidence of intra‐abdominal abscess of 11.8% (7/59); the overall leak rate was 3.4% (2/59). The re‐operation rate was 3.4% (2/59). A video included in the Supporting Information shows five different sites and techniques for ICA and describes technical details with tips and tricks. All patients shown in the video had an uneventful postoperative recovery and were managed postoperatively according to enhanced recovery after surgery protocols.
Conclusion
This case series illustrates all possible sites and techniques for colonic ICA in an emergency setting. All colorectal and acute care surgeons should have laparoscopic suturing skills.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Numerous neuropeptides were studied in different invertebrate species, but the presence of most of them was evaluated only by an immunocytochemical approach using antibodies against the vertebrate ...homologues. As a consequence, several authors referred to the presence of neuropeptide-like molecules. In view of the availability of numerous wholly sequenced invertebrate genomes, here we reviewed the data on the gene sequence and the related structure of four neuropeptides (corticotrophin-releasing hormone, tachykinins, bombesin and insulin) in invertebrates, analyzing their functions in comparison to what reported in vertebrates.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Global warming represents a substantial challenge on a broad range of organisms with diverse life-history traits and geographical distributions. Up till now several studies correlated global warming ...to changes in body mass, growth rate or fat content, whereas the effects on immune function and microbiota composition remained almost unexplored. On the contrary, some pioneering studies are showing that increased temperature may influence the insect immune function and the microbiota composition, making global warming in a pivotal position influencing insect survival and adaptation to a warming planet.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The function of DNA methylation has been investigated in depth in vertebrate and plant genomes, establishing that it is involved in gene silencing and transposon control. Data regarding insect ...methylation, even if still scanty, apparently argue against evolutionary conservation of DNA methylation functions. Cytosine methylation, therefore, proves to be an epigenetic tool repeatedly used to accomplish different functions in different taxa according to a sort of epigenetic tinkering occurring during evolution.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UL, UM, UPUK, VKSCE, ZAGLJ
A careful measure of fitness represents a crucial target in crop pest management and becomes fundamental considering extremely prolific insects. In the present paper, we describe a standardized ...rearing protocol and a bioinformatics tool to calculate aphid fitness indices and invasiveness starting from life table data. We tested the protocol and the bioinformatic tool using six Myzus persicae (Sulzer) asexual lineages in order to investigate if karyotype rearrangements and ecotype could influence their reproductive performances. The tool showed that different karyotypes do not influence adaptive success and put in evidence a marked invasive potential of the M. persicae lineage 64. The presence of a similar fitness rate of 33H and 7GK asexual lineages (both possessing intra-individual karyotype variations) in respect to the asexual lineage 1 (with a standard karyotype) represents an important demonstration of the potentiality of holocentric chromosomes to reduce the effects of chromosome rearrangements.
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