Vital genes in the heterochromatin of chromosomes 2 and 3 of Drosophila melanogaster

Heterochromatin has been traditionally regarded as a genomic wasteland, but in the last three decades extensive genetic and molecular studies have shown that this ubiquitous component of eukaryotic chromosomes may perform important biological functions. In D. melanogaster, about 30 genes that are essential for viability and/or fertility have been mapped to the heterochromatin of the major autosomes. Thus far, the known essential genes exhibit a peculiar molecular organization. They consist of single-copy exons, while their introns are comprised mainly of degenerate transposons. Moreover, about one hundred predicted genes that escaped previous genetic analyses have been associated with the proximal regions of chromosome arms but it remains to be determined how many of these genes are actually located within the heterochromatin. In this overview, we present available data on the mapping, molecular organization and function of known vital genes embedded in the heterochromatin of chromosomes 2 and 3. Repetitive loci, such as Responder and the ABO elements, which are also located in the heterochromatin of chromosome 2, are not discussed here because they have been reviewed in detail elsewhere.     

Defined media for vitrification,warming, and rehydration: effects on post-thaw protein synthesis and viability of in vitro derived ovine embryos

The purpose of this study was to assess the viability (rates of re-expanding and hatching in vitro), of in vitro derived ovine blastocysts using vitrification and warming/rehydration media containing fetal calf serum (20% FCS) or polyvinyl alcohol (0.1% PVA), and the incorporation of labelled methionine in protein synthesised during the first 4h after cryopreservation. In experiment 1, after 60 h culture in TCM-199 supplemented with 10% FCS, the hatching rates of blastocysts that had been vitrified, warmed, and rehydrated in media containing only PVA (p/p) were significantly (P<0.05) lower than those vitrified in medium containing PVA with warming and rehydration in medium containing FCS (p/s). Blastocysts that were vitrified in medium containing FCS and warmed and rehydrated in medium with PVA (s/p) had hatching rates that were significantly lower (P<0.01) than those vitrified, warmed, and rehydrated in media with only FCS (s/s). After warming, the number of dead cells in the p/p group was significantly (P<0.05) lower than in all other groups. In experiment 2, the [35S]methionine uptake by embryonic cells of the s/p group was significantly (P<0.01) higher than in other groups. The incorporation of labelled methionine into newly synthesised proteins was significantly lower in the p/p group (P<0.01) than in all other groups. No differences in the newly synthesised proteins were observed between groups. In conclusion, these results suggest that it is possible to replace serum with defined macromolecules in vitrification and warming/rehydration media for in vitro derived ovine blastocysts but this leads to a decrease in viability and a reduction in protein synthesis after warming.     

Serological immunoreactivity against colon cancer proteome varies upon disease progression

Sera from colon carcinoma patients were used to identify tumor-associated antigens (TAAs) by screening tumor proteome resolved by 2D electrophoresis. A panel of six TAAs eliciting a serological immune response in colorectal cancer was identified, showing a modification in antigen recognition by B cells in patients as a function of colon cancer progression. The expression of these proteins was either confined or increased in tumor as compared to normal mucosa.     

COVID-19 vaccination in Sindh Province,Pakistan: A modelling study of health impact and cost-effectiveness

BackgroundMultiple Coronavirus Disease 2019 (COVID-19) vaccines appear to be safe and efficacious, but only high-income countries have the resources to procure sufficient vaccine doses for most of their eligible populations. The World Health Organization has published guidelines for vaccine prioritisation, but most vaccine impact projections have focused on high-income countries, and few incorporate economic considerations. To address this evidence gap, we projected the health and economic impact of different vaccination scenarios in Sindh Province, Pakistan (population: 48 million).Methods and findingsWe fitted a compartmental transmission model to COVID-19 cases and deaths in Sindh from 30 April to 15 September 2020. We then projected cases, deaths, and hospitalisation outcomes over 10 years under different vaccine scenarios. Finally, we combined these projections with a detailed economic model to estimate incremental costs (from healthcare and partial societal perspectives), disability-adjusted life years (DALYs), and incremental cost-effectiveness ratio (ICER) for each scenario.We project that 1 year of vaccine distribution, at delivery rates consistent with COVAX projections, using an infection-blocking vaccine at $3/dose with 70% efficacy and 2.5-year duration of protection is likely to avert around 0.9 (95% credible interval (CrI): 0.9, 1.0) million cases, 10.1 (95% CrI: 10.1, 10.3) thousand deaths, and 70.1 (95% CrI: 69.9, 70.6) thousand DALYs, with an ICER of $27.9 per DALY averted from the health system perspective. Under a broad range of alternative scenarios, we find that initially prioritising the older (65+) population generally prevents more deaths. However, unprioritised distribution has almost the same cost-effectiveness when considering all outcomes, and both prioritised and unprioritised programmes can be cost-effective for low per-dose costs. High vaccine prices ($10/dose), however, may not be cost-effective, depending on the specifics of vaccine performance, distribution programme, and future pandemic trends.The principal drivers of the health outcomes are the fitted values for the overall transmission scaling parameter and disease natural history parameters from other studies, particularly age-specific probabilities of infection and symptomatic disease, as well as social contact rates. Other parameters are investigated in sensitivity analyses.This study is limited by model approximations, available data, and future uncertainty. Because the model is a single-population compartmental model, detailed impacts of nonpharmaceutical interventions (NPIs) such as household isolation cannot be practically represented or evaluated in combination with vaccine programmes. Similarly, the model cannot consider prioritising groups like healthcare or other essential workers. The model is only fitted to the reported case and death data, which are incomplete and not disaggregated by, e.g., age. Finally, because the future impact and implementation cost of NPIs are uncertain, how these would interact with vaccination remains an open question.ConclusionsCOVID-19 vaccination can have a considerable health impact and is likely to be cost-effective if more optimistic vaccine scenarios apply. Preventing severe disease is an important contributor to this impact. However, the advantage of prioritising older, high-risk populations is smaller in generally younger populations. This reduction is especially true in populations with more past transmission, and if the vaccine is likely to further impede transmission rather than just disease. Those conditions are typical of many low- and middle-income countries.

In a modelling study, Carl A B Pearson and coauthors investigate the health impact and cost-effectiveness of various COVID-19 vaccination scenarios in Sindh Province, Pakistan     

Computational annotation of genes differentially expressed along olive fruit development

Background  

Olea europaea L. is a traditional tree crop of the Mediterranean basin with a worldwide economical high impact. Differently from other fruit tree species, little is known about the physiological and molecular basis of the olive fruit development and a few sequences of genes and gene products are available for olive in public databases. This study deals with the identification of large sets of differentially expressed genes in developing olive fruits and the subsequent computational annotation by means of different software.     

GnRH antagonist enhance follicular growth in FSH-treated sheep but affect developmental competence of oocytes collected by ovum pick-up

This study evaluates the in vitro developmental competence of oocytes collected by ovum pick up (OPU) from sheep treated with GnRH antagonists (GnRHa) and high doses of FSH. Eighteen Sarda ewes were treated with progestagen sponges (day 0). On day 7, 10 ewes received 3 mg of GnRHa s.c., while 8 served as control receiving saline. On day 10, all animals were treated with 96 IU of ovine FSH in four equal doses given i.m. every 12 h. We monitored follicular development by ultrasonography, twice daily from day 7 to 11, and found that GnRHa induced a significant increase in the number of total follicles in 72 h (11.7+/-0.9 to 21+/-2.4, r(2)=0.598, P<0.0001), while this number remained stable in control sheep. We found that FSH induced a significant rise in the number of follicles in both groups; but always higher (P<0.05) in GnRHa treated sheep, confirming that GnRHa enhances ovarian response to exogenous FSH stimulation. Twelve hours after the last FSH dose, oocytes were collected by OPU. Recovery percentage, morphological quality, ability to resume meiosis, fertilization and cleavage were similar in oocytes from treated and untreated sheep. However, the final blastocysts output was lower in GnRHa group (10.1% versus 27.4% in control group; P<0.05). In addition, re-expansion rates after vitrification, thawing and in vitro culture were lower in GnRHa treated ewes, although differences did not reach statistical significance (55.5% versus 74.1% in GnRHa treated and in control sheep, respectively).     

Overexpression of gastrokine 1 in gastric cancer cells induces Fas-mediated apoptosis

Gastrokine 1 (GKN1) is involved in the replenishment of the surface lumen epithelial cell layer, in maintaining the mucosal integrity, and could play a role in cell proliferation and differentiation. In fact, after injury of the gastric mucosa, restoration may occur very rapidly in the presence of GKN1. In contrast, if the protein is downregulated, the repair process may be hampered; however, application of GKN1 to gastrointestinal cells promoted epithelial restoration. Because GKN1 possesses some mitogenic effects on intestinal epithelial cells (IEC-6) whereas this protein was also capable of inhibiting proliferation in gastric cancer cells (MKN28), we decided to study its involvement in apoptosis to understand the role of GKN1 in the modulation of inflammatory damage or tumorigenesis in gastric mucosa. We found by cytofluorimetry, Western blot and RT-PCR that the overexpression of GKN1 in gastric cancer cell lines (AGS and MKN28) stimulated the expression of Fas receptor. Moreover, compared to control cells, a significant increase of apoptosis, evaluated by TUNEL, was observed when GKN1 transfected cells were treated with a monoclonal antibody (IgM) anti-Fas. The activation of Fas expression was also observed by the overexpression of GKN1 in other cancer cell lines. Moreover, in GKN1-overexpressing gastric cancer cells exposed to FasL, the activation of caspase-3 was also observed by Western blot and fluorescence assays. Our data represent the first report for GKN1 as modulator of apoptotic signals and suggest that GKN1 might play an important role for tissue repair during the early stages of neoplastic transformation.     

Detection and characterization of Mycoplasma spp. and Salmonella spp. in free-living European tortoises (Testudo hermanni, Testudo graeca, and Testudo marginata)

Free-living and captive chelonians might suffer from upper respiratory tract disease (URTD), a pathology primarily caused by Mycoplasma agassizii. Wild tortoises can also be an important reservoir of Salmonella spp., which are commensal in the host reptile but are potential zoonotic agents. Between July 2009 and June 2010, we screened free-living European tortoises (spur-thighed tortoises Testudo graeca, Hermann's tortoises Testudo hermanni, marginated tortoises Testudo marginata) temporarily housed in a wildlife center in Italy. We molecularly characterized 13 Mycoplasma isolates detected in all Testudo spp. studied, and three PCR-positive animals showed typical URTD clinical signs at the time of sampling. Three Salmonella enterica serotypes (Abony, Potsdam, Granlo), already related to reptile-associated human infections, were also identified. These results highlight the potential role played by wildlife recovery centers in the spread and transmission of pathogens among wild chelonians and to humans.     

Effect of storage temperature during transport of ovaries on in vitro embryo production in Iberian red deer (Cervus elaphus hispanicus)

The aim of this work was to study the effect of storage temperature during the transport of ovaries on cleavage and blastocyst rates in Iberian red deer, because wild populations of this subspecies are usually far from laboratories. A total of 472 ovaries from 236 Iberian hinds were recovered and maintained in saline solution at 5-8 °C or 20-25 °C for 12 h. After storage, aspirated oocytes were matured with FSH/LH or EGF and the developed embryos were cultured with oviduct epithelial cells monolayer (OCM). A higher (P = 0.009) cleavage rate was obtained when the ovaries were stored at 5-8 °C. However, there were no differences between both storage temperatures in relation to the percentage of blastocysts obtained. Considering the management and production systems of Iberian red deer, this study provides important information about the ovary storage temperature during transport with the purpose of assuring an optimal in vitro embryo production.