Cancer cells, including melanoma cells, often metastasize regionally through the lymphatic system before metastasizing systemically through the blood
; however, the reason for this is unclear. Here ...we show that melanoma cells in lymph experience less oxidative stress and form more metastases than melanoma cells in blood. Immunocompromised mice with melanomas derived from patients, and immunocompetent mice with mouse melanomas, had more melanoma cells per microlitre in tumour-draining lymph than in tumour-draining blood. Cells that metastasized through blood, but not those that metastasized through lymph, became dependent on the ferroptosis inhibitor GPX4. Cells that were pretreated with chemical ferroptosis inhibitors formed more metastases than untreated cells after intravenous, but not intralymphatic, injection. We observed multiple differences between lymph fluid and blood plasma that may contribute to decreased oxidative stress and ferroptosis in lymph, including higher levels of glutathione and oleic acid and less free iron in lymph. Oleic acid protected melanoma cells from ferroptosis in an Acsl3-dependent manner and increased their capacity to form metastatic tumours. Melanoma cells from lymph nodes were more resistant to ferroptosis and formed more metastases after intravenous injection than did melanoma cells from subcutaneous tumours. Exposure to the lymphatic environment thus protects melanoma cells from ferroptosis and increases their ability to survive during subsequent metastasis through the blood.
The electrochemical N2 reduction reaction (NRR) offers a direct pathway to produce NH3 from renewable energy. However, aqueous NRR suffers from both low Faradaic efficiency (FE) and low yield rate. ...The main reason is the more favored H+ reduction to H2 in aqueous electrolytes. Here we demonstrate a highly selective Ru/MoS2 NRR catalyst on which the MoS2 polymorphs can be controlled to suppress H+ reduction. A NRR FE as high as 17.6% and NH3 yield rate of 1.14 × 10–10 mol cm–2 s–1 are demonstrated at 50 °C. Theoretical evidence supports a hypothesis that the high NRR activity originates from the synergistic interplay between the Ru clusters as N2 binding sites and nearby isolated S-vacancies on the 2H-MoS2 as centers for hydrogenation; this supports formation of NH3 at the Ru/2H-MoS2 interface.
Abstract
Background
The authors investigated the durability of vaccine efficacy (VE) against human papillomavirus (HPV)16 or 18 infections and antibody response among nonrandomly assigned women who ...received a single dose of the bivalent HPV vaccine compared with women who received multiple doses and unvaccinated women.
Methods
HPV infections were compared between HPV16 or 18-vaccinated women aged 18 to 25 years who received one (N = 112), two (N = 62), or three (N = 1365) doses, and age- and geography-matched unvaccinated women (N = 1783) in the long-term follow-up of the Costa Rica HPV Vaccine Trial. Cervical HPV infections were measured at two study visits, approximately 9 and 11 years after initial HPV vaccination, using National Cancer Institute next-generation sequencing TypeSeq1 assay. VE and 95% confidence intervals (CIs) were estimated. HPV16 or 18 antibody levels were measured in all one- and two-dose women, and a subset of three-dose women, using a virus-like particle-based enzyme-linked immunosorbent assay (n = 448).
Results
Median follow-up for the HPV-vaccinated group was 11.3 years (interquartile range = 10.9–11.7 years) and did not vary by dose group. VE against prevalent HPV16 or 18 infection was 80.2% (95% CI = 70.7% to 87.0%) among three-dose, 83.8% (95% CI = 19.5% to 99.2%) among two-dose, and 82.1% (95% CI = 40.2% to 97.0%) among single-dose women. HPV16 or 18 antibody levels did not qualitatively decline between years four and 11 regardless of the number of doses given, although one-dose titers continue to be statistically significantly lower compared with two- and three-dose titers.
Conclusion
More than a decade after HPV vaccination, single-dose VE against HPV16 or 18 infection remained high and HPV16 or 18 antibodies remained stable. A single dose of bivalent HPV vaccine may induce sufficiently durable protection that obviates the need for more doses.
Genetic deletion of the mitochondrial deacetylase sirtuin-3 (
Sirt3) results in increased mitochondrial superoxide, a tumor-permissive environment, and mammary tumor development. MnSOD contains a ...nutrient- and ionizing radiation (IR)-dependent reversible acetyl-lysine that is hyperacetylated in Sirt3
−
/− livers at 3 months of age. Livers of Sirt3
−/− mice exhibit decreased MnSOD activity, but not immunoreactive protein, relative to wild-type livers. Reintroduction of wild-type but not deacetylation null
Sirt3 into Sirt3
−/− MEFs deacetylated lysine and restored MnSOD activity. Site-directed mutagenesis of MnSOD lysine 122 to an arginine, mimicking deacetylation (lenti-MnSOD
K122-R), increased MnSOD activity when expressed in MnSOD
−/− MEFs, suggesting acetylation directly regulates function. Furthermore, infection of Sirt3
−/− MEFs with lenti-MnSOD
K122-R inhibited in vitro immortalization by an oncogene (
Ras), inhibited IR-induced genomic instability, and decreased mitochondrial superoxide. Finally, IR was unable to induce MnSOD deacetylation or activity in Sirt3
−/− livers, and these irradiated livers displayed significant IR-induced cell damage and microvacuolization in their hepatocytes.
► Mitochondrial Sirt3 deacetylates MnSOD after fasting and radiation ► MnSOD contains a reversible acetyl-lysine at amino acid 122 ► MnSOD lysine 122 acetylation regulates enzymatic activity ►
Sirt3 knockout mice have a radiation damage liver phenotype
Analysis of blood for the evaluation of clinically relevant biomarkers requires precise collection and sample handling by phlebotomists and laboratory staff. An important consideration for the ...clinical application of metabolomics are the different anticoagulants utilized for sample collection. Most studies that have characterized differences in metabolite levels in various blood collection tubes have focused on single analytes. We define analyte levels on a global metabolomics platform following blood sampling using five different, but commonly used, clinical laboratory blood collection tubes (i.e., plasma anticoagulated with either EDTA, lithium heparin or sodium citrate, along with no additive (serum), and EDTA anticoagulated whole blood).
Using an untargeted metabolomics platform we analyzed five sample types after all had been collected and stored at -80°C. The biochemical composition was determined and differences between the samples established using matched-pair t-tests.
We identified 1,117 biochemicals across all samples and detected a mean of 1,036 in the sample groups. Compared to the levels of metabolites in EDTA plasma, the number of biochemicals present at statistically significant different levels (p<0.05) ranged from 452 (serum) to 917 (whole blood). Several metabolites linked to screening assays for rare diseases including acylcarnitines, bilirubin and heme metabolites, nucleosides, and redox balance metabolites varied significantly across the sample collection types.
Our study highlights the widespread effects and importance of using consistent additives for assessing small molecule levels in clinical metabolomics. The biochemistry that occurs during the blood collection process creates a reproducible signal that can identify specimens collected with different anticoagulants in metabolomic studies.
In this manuscript, normal/healthy donors had peripheral blood collected using multiple anticoagulants as well as serum during a fasted blood draw. Global metabolomics is a new technology being utilized to draw clinical conclusions and we interrogated the effects of different anticoagulants on the levels of biochemicals from each of the donors. Characterizing the effects of the anticoagulants on biochemical levels will help researchers leverage the information using global metabolomics in order to make conclusions regarding important disease biomarkers.
The mouse X-inactivation center (Xic) locus represents a powerful model for understanding the links between genome architecture and gene regulation, with the non-coding genes Xist and Tsix showing ...opposite developmental expression patterns while being organized as an overlapping sense/antisense unit. The Xic is organized into two topologically associating domains (TADs) but the role of this architecture in orchestrating cis-regulatory information remains elusive. To explore this, we generated genomic inversions that swap the Xist/Tsix transcriptional unit and place their promoters in each other's TAD. We found that this led to a switch in their expression dynamics: Xist became precociously and ectopically upregulated, both in male and female pluripotent cells, while Tsix expression aberrantly persisted during differentiation. The topological partitioning of the Xic is thus critical to ensure proper developmental timing of X inactivation. Our study illustrates how the genomic architecture of cis-regulatory landscapes can affect the regulation of mammalian developmental processes.
Abstract
Background
The Costa Rica HPV Vaccine Trial has documented cross-protection of the bivalent HPV vaccine against HPV31/33/45 up to 7 years after vaccination, even with one dose of the ...vaccine. However, the durability of such protection remains unknown. Here, we evaluate the efficacy of different schedules of the vaccine against HPV31/33/45 out to 11 years postvaccination, expanding to other nontargeted HPV types.
Methods
We compared the rates of HPV infection in vaccinated women with the rates in a comparable cohort of unvaccinated women. We estimated the average vaccine efficacy (VEavg) against incident infections and tested for a change in VE over time.
Results
Among 3-dose women, we observed statistically significant cross-protection against HPV31/33/45 (VEavg = 64.4%, 95% confidence interval CI = 57.7% to 70.0%). Additionally, we observed borderline, statistically significant cross-protection against HPV35 (VEavg = 23.2%, 95% CI = 0.3% to 40.8%) and HPV58 (VEavg = 21.2%, 95% CI = 4.2% to 35.3%). There was no decrease in VE over time (two-sided Ptrend > .05 for HPV31, -33, -35, -45, and -58). As a benchmark, VEavg against HPV16/18 was 82.0% (95% CI = 77.3% to 85.7%). Among 1-dose women, we observed comparable efficacy against HPV31/33/45 (VEavg = 54.4%, 95% CI = 21.0% to 73.7%). Acquisition of nonprotected HPV types was similar between vaccinated and unvaccinated women, indicating that the difference in HPV infection rates was not attributable to differential genital HPV exposure.
Conclusions
Substantial cross-protection afforded by the bivalent vaccine against HPV31/33/45, and to a lesser extent, HPV35 and HPV58, was sustained and remained stable after 11 years postvaccination, reinforcing the notion that the bivalent vaccine is an effective option for protection against HPV-associated cancers.
Silicon-based impurities are ubiquitous in natural graphite. However, their role as a contaminant in exfoliated graphene and their influence on devices have been overlooked. Herein atomic resolution ...microscopy is used to highlight the existence of silicon-based contamination on various solution-processed graphene. We found these impurities are extremely persistent and thus utilising high purity graphite as a precursor is the only route to produce silicon-free graphene. These impurities are found to hamper the effective utilisation of graphene in whereby surface area is of paramount importance. When non-contaminated graphene is used to fabricate supercapacitor microelectrodes, a capacitance value closest to the predicted theoretical capacitance for graphene is obtained. We also demonstrate a versatile humidity sensor made from pure graphene oxide which achieves the highest sensitivity and the lowest limit of detection ever reported. Our findings constitute a vital milestone to achieve commercially viable and high performance graphene-based devices.
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