Dzyaloshinskii-Moriya Interaction and Spiral Order in Spin-orbit Coupled Optical Lattices

We show that the recent experimental realization of spin-orbit coupling in ultracold atomic gases can be used to study different types of spin spiral order and resulting multiferroic effects. Spin-orbit coupling in optical lattices can give rise to the Dzyaloshinskii-Moriya (DM) spin interaction which is essential for spin spiral order. By taking into account spin-orbit coupling and an external Zeeman field, we derive an effective spin model in the Mott insulator regime at half filling and demonstrate that the DM interaction in optical lattices can be made extremely strong with realistic experimental parameters. The rich finite temperature phase diagrams of the effective spin models for fermions and bosons are obtained via classical Monte Carlo simulations.Comment: 7 pages, 5 figure

Synchronized cycles of bacterial lysis for in vivo delivery

The pervasive view of bacteria as strictly pathogenic has given way to an ppreciation of the widespread prevalence of beneficial microbes within the human body. Given this milieu, it is perhaps inevitable that some bacteria would evolve to preferentially grow in environments that harbor disease and thus provide a natural platform for the development of engineered therapies. Such therapies could benefit from bacteria that are programmed to limit bacterial growth while continually producing and releasing cytotoxic agents in situ. Here, we engineer a clinically relevant bacterium to lyse synchronously at a threshold population density and to release genetically encoded cargo. Following quorum lysis, a small number of surviving bacteria reseed the growing population, thus leading to pulsatile delivery cycles. We use microfluidic devices to characterize the engineered lysis strain and we demonstrate its potential as a drug deliver platform via co-culture with human cancer cells in vitro. As a proof of principle, we track the bacterial population dynamics in ectopic syngeneic colorectal tumors in mice. The lysis strain exhibits pulsatile population dynamics in vivo, with mean bacterial luminescence that remained two orders of magnitude lower than an unmodified strain. Finally, guided by previous findings that certain bacteria can enhance the efficacy of standard therapies, we orally administer the lysis strain, alone or in combination with a clinical chemotherapeutic, to a syngeneic transplantation model of hepatic colorectal metastases. We find that the combination of both circuit-engineered bacteria and chemotherapy leads to a notable reduction of tumor activity along with a marked survival benefit over either therapy alone. Our approach establishes a methodology for leveraging the tools of synthetic biology to exploit the natural propensity for certain bacteria to colonize disease sites.National Institute of General Medical Sciences (U.S.) (GM069811)San Diego Center for Systems Biology (P50 GM085764)National Cancer Institute (U.S.). Swanson Biotechnology Center (Koch Institute Support Grant (P30-CA14051))National Institute of Environmental Health Sciences (Core Center Grant (P30- ES002109))National Institutes of Health (U.S.) (NIH Pathway to Independence Award NIH (K99 CA197649-01))Misrock Postdoctoral fellowshipNational Defense Science and Engineering Graduate (NDSEG) Fellowshi

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Stability of Piceatannol in Dulbecco's Modified Eagle's Medium by In Situ UPLC-MS/MS Analysis

Piceatannol is a stilbenoid, which has shown bioactivities in various cell culture models. However, its stability in cell culture medium is not clear. Here, UPLC-MS/MS was applied in situ to analyze the degradation products of piceatannol in Dulbecco's Modified Eagle's Medium (DMEM) and cell culture to investigate the compound's stability in DMEM. During the incubation with cell culture medium (at 4 and 37 °C), several piceatannol derivatives, such as an oxidation product ( m/z 243.06), a reduction product ( m/z 247.09), dimers ( m/z 485.12 and 487.14) and trimers ( m/z 727.18) were detected, which demonstrated the instability of piceatannol in cell culture conditions. To confirm if the new products during the incubation were generated due to the instability of piceatannol, ascorbic acid was added. The presence of ascorbic acid could significantly slow the degradation rate of piceatannol and the generation of piceatannol derivatives, which proved that the new products were generated by the degradation of piceatannol and indicated that the instability of piceatannol might be related to its antioxidant activity

Lymphopenia is an important prognostic factor in peripheral T-cell lymphoma (NOS) treated with anthracycline-containing chemotherapy.

BACKGROUND: Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a heterogeneous group of aggressive T-cell lymphomas with poor treatment outcomes. The aim of this study was to evaluate whether lymphopenia at diagnosis would have an adverse effect on survival in patients with PTCL-NOS treated with anthracycline-containing chemotherapy. METHODS: A total of 118 patients with PTCL-NOS treated with anthracycline-containing chemotherapy from 4 Korean institutions were included. RESULTS: Thirty-six patients (30.5%) had a low absolute lymphocyte count (ALC, < 1.0 × 109/L) at diagnosis. Patients with lymphopenia had shorter overall survival (OS) and progression-free survival (PFS) rates compared with patients with high ALCs (P = 0.003, P = 0.012, respectively). In multivariate analysis, high-intermediate/high-risk International Prognostic Index (IPI) scores and lymphopenia were both associated with shorter OS and PFS. Treatment-related mortality was 25.0% in the low ALC group and 4.8% in the high ALC group (P = 0.003). In patients considered high-intermediate/high-risk based on IPI scores, lymphopenia was also associated with shorter OS and PFS (P = 0.002, P = 0.001, respectively). CONCLUSION: This study suggests that lymphopenia could be an independent prognostic marker to predict unfavorable OS and PFS in patients with PTCL-NOS treated with anthracycline-containing chemotherapy and can be used to further stratify high-risk patients using IPI scores

Comparative safety analysis of mRNA and adenoviral vector COVID-19 vaccines: a nationwide cohort study using an emulated target trial approach

Objective: This nationwide cohort study compared the incidence of adverse events of special interest (AESIs) between adenoviral vector-based (ChAdOx1) and mRNA-based (BNT162b2 or mRNA-1273) coronavirus disease 2019 (COVID-19) vaccines. Methods: A targeted trial emulation study was conducted using data from the National Health Insurance Service database. Vaccinees aged 18–85 years who had received at least one dose of ChAdOx1 or an mRNA-based vaccine were identified. The 42-day risks of AESIs were calculated. Results: A total of 1 767 539 ChAdOx1 vaccinees were matched exactly with mRNA vaccinees according to their risk factors. The 42-day risks of adverse events were low (∼0 to 176 events per 100 000 persons in both vaccine groups), and the incidence rates of AESIs were comparable between the two platforms, except for a higher occurrence of acute cardiac injury (incidence rate ratio [IRR], 1.22; 95% CI, 1.10–1.35), myocarditis or pericarditis (IRR, 2.14; 95% CI, 1.14–4.04), and arrhythmia (IRR, 1.46; 95% CI, 1.24–1.71) in mRNA vaccinees. The incidence of Guillain–Barré syndrome (IRR, 0.20; 95% CI, 0.06–0.69), vasovagal syncope (IRR, 0.77; 95% CI, 0.62–0.97), radiculopathy (IRR = 0.59, 95% CI, 0.41–0.84), and aseptic arthritis (IRR, 0.81; 95% CI, 0.70–0.93) was significantly lower in mRNA-based vaccinees compared with ChAdOx1 vaccinees. Discussion: A remarkable platform-dependent difference was observed in the safety profiles of COVID-19 vaccines, particularly for myocarditis or pericarditis and Guillain–Barré syndrome. However, the overall risk of AESIs was low for both vaccine platforms

Clinical outcomes and prognostic factors of empirical antifungal therapy with itraconazole in the patients with hematological malignancies: a prospective multicenter observational study in Korea.

PURPOSE: To identify prognostic factors for the outcomes of empirical antifungal therapy, we performed a multicenter, prospective, observational study in immunocompromised patients with hematological malignancies. MATERIALS AND METHODS: Three hundred seventy-six patients (median age of 48) who had neutropenic fever and who received intravenous (IV) itraconazole as an empirical antifungal therapy for 3 or more days were analyzed. The patients with possible or probable categories of invasive fungal disease (IFD) were enrolled. RESULTS: The overall success rate was 51.3% (196/376). Age >50 years, underlying lung disease (co-morbidity), poor performance status [Eastern Cooperative Oncology Group (ECOG) >/=2], radiologic evidence of IFD, longer duration of baseline neutropenic fever (>/=4 days), no antifungal prophylaxis or prophylactic use of antifungal agents other than itraconazole, and high tumor burden were associated with decreased success rate in univariate analysis. In multivariate analysis, age >50 years (p=0.009) and poor ECOG performance status (p=0.005) were significantly associated with poor outcomes of empirical antifungal therapy. Twenty-two patients (5.9%) discontinued itraconazole therapy due to toxicity. CONCLUSION: We concluded that empirical antifungal therapy with IV itraconazole in immunocompromised patients is effective and safe. Additionally, age over 50 years and poor performance status were poor prognostic factors for the outcomes of empirical antifungal therapy with IV itraconazole

Applying two-photon excitation fluorescence lifetime imaging microscopy to study photosynthesis in plant leaves

This study investigates to which extent two-photon excitation (TPE) fluorescence lifetime imaging microscopy can be applied to study picosecond fluorescence kinetics of individual chloroplasts in leaves. Using femtosecond 860 nm excitation pulses, fluorescence lifetimes can be measured in leaves of Arabidopsis thaliana and Alocasia wentii under excitation-annihilation free conditions, both for the F0- and the Fm-state. The corresponding average lifetimes are ~250 ps and ~1.5 ns, respectively, similar to those of isolated chloroplasts. These values appear to be the same for chloroplasts in the top, middle, and bottom layer of the leaves. With the spatial resolution of ~500 nm in the focal (xy) plane and 2 μm in the z direction, it appears to be impossible to fully resolve the grana stacks and stroma lamellae, but variations in the fluorescence lifetimes, and thus of the composition on a pixel-to-pixel base can be observed

Chronic kidney disease, severe arterial and arteriolar sclerosis and kidney neoplasia: on the spectrum of kidney involvement in MELAS syndrome

<p>Abstract</p> <p>Background</p> <p>MELAS syndrome (MIM ID#540000), an acronym for Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-like episodes, is a genetically heterogeneous mitochondrial disorder with protean manifestations and occasional kidney involvement. Interest in the latter is rising due to the identification of cases with predominant kidney involvement and to the hypothesis of a link between mitochondrial DNA and kidney neoplasia.</p> <p>Case presentation</p> <p>We report the case of a 41-year-old male with full blown MELAS syndrome, with lactic acidosis and neurological impairment, affected by the "classic" 3243A > G mutation of mitochondrial DNA, with kidney cancer. After unilateral nephrectomy, he rapidly developed severe kidney functional impairment, with nephrotic proteinuria. Analysis of the kidney tissue at a distance from the two tumor lesions, sampled at the time of nephrectomy was performed in the context of normal blood pressure, recent onset of diabetes and before the appearance of proteinuria. The morphological examination revealed a widespread interstitial fibrosis with dense inflammatory infiltrate and tubular atrophy, mostly with thyroidization pattern. Vascular lesions were prominent: large vessels displayed marked intimal fibrosis and arterioles had hyaline deposits typical of hyaline arteriolosclerosis. These severe vascular lesions explained the different glomerular alterations including ischemic and obsolescent glomeruli, as is commonly observed in the so-called "benign" arteriolonephrosclerosis. Some rare glomeruli showed focal segmental glomerulosclerosis; as the patient subsequently developed nephrotic syndrome, these lesions suggest that silent ischemic changes may result in the development of focal segmental glomerulosclerosis secondary to nephron loss.</p> <p>Conclusions</p> <p>Nephron loss may trigger glomerular sclerosis, at least in some cases of MELAS-related nephropathy. Thus the incidence of kidney disease in the "survivors" of MELAS syndrome may increase as the support therapy of these patients improves.</p

Reference gene validation for quantitative RT-PCR during biotic and abiotic stresses in Vitis vinifera

Grapevine is one of the most cultivated fruit crop worldwide with Vitis vinifera being the species with the highest economical importance. Being highly susceptible to fungal pathogens and increasingly affected by environmental factors, it has become an important agricultural research area, where gene expression analysis plays a fundamental role. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is currently amongst the most powerful techniques to perform gene expression studies. Nevertheless, accurate gene expression quantification strongly relies on appropriate reference gene selection for sample normalization. Concerning V. vinifera, limited information still exists as for which genes are the most suitable to be used as reference under particular experimental conditions. In this work, seven candidate genes were investigated for their stability in grapevine samples referring to four distinct stresses (Erysiphe necator, wounding and UV-C irradiation in leaves and Phaeomoniella chlamydospora colonization in wood). The expression stability was evaluated using geNorm, NormFinder and BestKeeper. In all cases, full agreement was not observed for the three methods. To provide comprehensive rankings integrating the three different programs, for each treatment, a consensus ranking was created using a non-weighted unsupervised rank aggregation method. According to the last, the three most suitable reference genes to be used in grapevine leaves, regardless of the stress, are UBC, VAG and PEP. For the P. chlamydospora treatment, EF1, CYP and UBC were the best scoring genes. Acquaintance of the most suitable reference genes to be used in grapevine samples can contribute for accurate gene expression quantification in forthcoming studiesinfo:eu-repo/semantics/publishedVersio