2,694 research outputs found

    A software approach to defeating side channels in last-level caches

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    We present a software approach to mitigate access-driven side-channel attacks that leverage last-level caches (LLCs) shared across cores to leak information between security domains (e.g., tenants in a cloud). Our approach dynamically manages physical memory pages shared between security domains to disable sharing of LLC lines, thus preventing "Flush-Reload" side channels via LLCs. It also manages cacheability of memory pages to thwart cross-tenant "Prime-Probe" attacks in LLCs. We have implemented our approach as a memory management subsystem called CacheBar within the Linux kernel to intervene on such side channels across container boundaries, as containers are a common method for enforcing tenant isolation in Platform-as-a-Service (PaaS) clouds. Through formal verification, principled analysis, and empirical evaluation, we show that CacheBar achieves strong security with small performance overheads for PaaS workloads

    Bumber landings of koth, Otolithoides biauritus by bottom set gill net at Satpati

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    Bumber catch of Koth, Otolithoides biauritus was reported on 19th December 2002 at Satpati. Koth was caught in 18-20 meter depths at a distance of 15-18 km north west off Satpati. The heavy concenteration indicates the potential fishing ground of koth in this region

    Dizajniranje i optimizacija mikrokapsula artemetera za maskiranje gorkog okusa

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    The objective of the present investigation was to reduce the bitterness of artemether (ARM). Microparticles were prepared by the coacervation method using Eudragit E 100 (EE) as polymer and sodium hydroxide solution as nonsolvent for the polymer. A 32 full factorial design was used for optimization wherein the amount of drug (A) and polymer (B) were selected as independent variables and the bitterness score, particle size and drug release at pH, 1.2 and 6.8 were selected as dependent variables. Optimization was carried out using the desirability function. The optimized microparticles batch was characterized by FT-IR and DSC. Multiple linear regression analysis revealed that reduced bitterness of ARM can be obtained by controlling the drug release of microparticles at pH 6.8 and increasing the amount of EE. The increase in the amount of polymer leads to reduction in drug release from microparticles at pH > 5 due to its insolubility and thus reduces bitterness. However, the increase in the amount of polymer results in improved dissolution, suggesting improved availability of ARM in stomach. Optimized microparticles prepared using 0.04 g of ARM and 15 mL of 1% m/V solution of EE showed complete bitter taste masking with improved drug release at pH 1.2.Cilja ovog rada je bio maskirati gorki okus artemetera (ARM) mikrokapsuliranjem. Mikročestice su pripravljene metodom koacervacije pomoću Eudragita E 100 (EE) kao polimerne komponente i natrijevog hidroksida u kojem se polimer ne otapa. 32 faktorijalni dizajn upotrebljen je za optimizaciju. Količine ljekovite tvari (A) i polimera (B) izabrane su kao nezavisne varijable, a intenzitet gorkog okusa, veličina čestica i oslobađanje ljekovite tvari pri pH 1,2 i 6,8 izabrane su kao zavisne varijable. Optimizirane mikročestice karakterizirane su pomoću FT-IR i DSC. Multipla linearna regresijska analiza otkrila je da se smanjenje gorčine artemetera može postići kontroliranjem oslobađanja ljekovite tvari pri pH 6,8 i povećanjem količine EE. Povećanje količine polimera dovodi do smanjenja oslobađanja ljekovite tvari pri pH > 5 pa se smanjuje i gorčina. Međutim, povećanje količine polimera povećava topljivost ljekovite tvari, a time potencijalno i njenu raspoložljivost u želucu. U optimiziranim mikročesticama pripravljenim pomoću 0,04 g ARM i 15 mL 1% m/v otopine EE potpuno se maskirao gorki okus, a oslobađanje ljekovite tvari pri pH 1,2 bilo je poboljšano

    Binuclear Manganese(III) Complexes as Electron Donors in D1/D2/Cytochrome b559 Preparations Isolated from Spinach Photosystem II Membrane Fragments

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    The capability of different manganese complexes to act as PS II electron donors in D1/D2/ cytochrome b 559 complexes has been analyzed by measuring actinic light-induced absorption changes at 680 nm (650 nm) and 340 nm, reflecting the photoaccumulation of Pheophytin- (Pheo-) and the reduction of NADP+ respectively. The data obtained reveal: a) the donor capacity of synthetic binuclear Mn(III)2 complexes containing aromatic ligands significantly exceeds that for MnCl2 in both cases, i.e. Pheo- photoaccumulation and NADP+ reduction; b) manganese complexes can serve as suitable electron donors for light-induced NADP+ reduction catalyzed by D1/D2/cytochrome b559 complexes and ferredoxin plus ferredoxin- NADP+ reductase under anaerobic conditions and c) the specific turnover rate of the system leading to NADP+ reduction is extremely small. The implications of these findings are briefly discussed

    Calcium and Vitamin D increase mRNA levels for the growth control hIK1 channel in human epidermal keratinocytes but functional channels are not observed

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    BACKGROUND: Intermediate-conductance, calcium-activated potassium channels (IKs) modulate proliferation and differentiation in mesodermal cells by enhancing calcium influx, and they contribute to the physiology of fluid movement in certain epithelia. Previous reports suggest that IK channels stimulate proliferative growth in a keratinocyte cell line; however, because these channels indirectly promote calcium influx, a critically unique component of the keratinocyte differentiation program, an alternative hypothesis is that they would be anti-proliferative and pro-differentiating. This study addresses these hypotheses. METHODS: Real-time PCR, patch clamp electrophysiology, and proliferation assays were used to determine if human IK1 (hIK1) expression and function are correlated with either proliferation or differentiation in cultured human skin epidermal keratinocytes, and skin biopsies grown in explant culture. RESULTS: hIK1 mRNA expression in human keratinocytes and skin was increased in response to anti-proliferative/pro-differentiating stimuli (elevated calcium and Vitamin D). Correspondingly, the hIK1 agonist 1-EBIO inhibited keratinocyte proliferation suggesting that the channel could be anti-proliferative and pro-differentiating. However, this proliferative inhibition by 1-EBIO was not reversed by a panel of hIK1 blockers, calling into question the mechanism of 1-EBIO action. Subsequent patch clamp electrophysiological analysis failed to detect hIK1 channel currents in keratinocytes, even those expressing substantial hIK1 mRNA in response to calcium and Vitamin D induced differentiation. Identical electrophysiological recording conditions were then used to observe robust IK1 currents in fibroblasts which express IK1 mRNA levels comparable to those of keratinocytes. Thus, the absence of observable hIK1 currents in keratinocytes was not a function of the electrophysiological techniques. CONCLUSION: Human keratinocyte differentiation is stimulated by calcium mobilization and influx, and differentiation stimuli coordinately upregulate mRNA levels of the calcium-activated hIK1 channel. This upregulation is paradoxical in that functional hIK1 channels are not observed in cultured keratinocytes. It appears, therefore, that hIK1 does not contribute to the functional electrophysiology of primary human keratinocytes, nor intact human skin. Further, the results indicate caution is required when interpreting experiments utilizing pharmacological hIK1 modulators in human keratinocytes

    Adjuvant Intravesical Chemohyperthermia Versus Passive Chemotherapy in Patients with Intermediate-risk Non–muscle-invasive Bladder Cancer (HIVEC-II): A Phase 2, Open-label, Randomised Controlled Trial

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    Background: Adjuvant intravesical chemotherapy following tumour resection is recommended for intermediate-risk non–muscle-invasive bladder cancer (NMIBC). Objective: To assess the efficacy and safety of adjuvant intravesical chemohyperthermia (CHT) for intermediate-risk NMIBC. Design, setting, and participants: HIVEC-II is an open-label, phase 2 randomised controlled trial of CHT versus chemotherapy alone in patients with intermediate-risk NMIBC recruited at 15 centres between May 2014 and December 2017 (ISRCTN 23639415). Randomisation was stratified by treating hospital. Interventions: Patients were randomly assigned (1:1) to adjuvant CHT with mitomycin C at 43°C or to room-temperature mitomycin C (control). Both treatment arms received six weekly instillations of 40 mg of mitomycin C lasting for 60 min. Outcome measurements and statistical analysis: The primary endpoint was 24-mo disease-free survival as determined via cystoscopy and urinary cytology. Analysis was by intention to treat. Results: A total of 259 patients (131 CHT vs 128 control) were randomised. At 24 mo, 42 patients (32%) in the CHT group and 49 (38%) in the control group had experienced recurrence. Disease-free survival at 24 mo was 61% (95% confidence interval [CI] 51–69%) in the CHT arm and 60% (95% CI 50–68%) in the control arm (hazard ratio [HR] 0.92, 95% CI 0.62–1.37; log-rank p = 0.8). Progression-free survival was higher in the control arm (HR 3.44, 95% CI 1.09–10.82; log-rank p = 0.02) on intention-to-treat analysis but was not significantly higher on per-protocol analysis (HR 2.87, 95% CI 0.83–9.98; log-rank p = 0.06). Overall survival was similar (HR 2.55, 95% CI 0.77–8.40; log-rank p = 0.09). Patients undergoing CHT were less likely to complete their treatment (n =75, 59% vs n = 111, 89%). Adverse events were reported by 164 patients (87 CHT vs 77 control). Major (grade III) adverse events were rare (13 CHT vs 7 control). Conclusions: CHT cannot be recommended over chemotherapy alone for intermediate-risk NMIBC. Adverse events following CHT were of low grade and short-lived, although patients were less likely to complete their treatment. Patient summary: The HIVEC-II trial investigated the role of heated chemotherapy instillations in the bladder for treatment of intermediate-risk non–muscle-invasive bladder cancer. We found no cancer control benefit from heated chemotherapy instillations over room-temperature chemotherapy. Adverse events following heated chemotherapy were low grade and short-lived, although these patients were less likely to complete their treatment

    Selective Processing and Metabolism of Disease-Causing Mutant Prion Proteins

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    Prion diseases are fatal neurodegenerative disorders caused by aberrant metabolism of the cellular prion protein (PrPC). In genetic forms of these diseases, mutations in the globular C-terminal domain are hypothesized to favor the spontaneous generation of misfolded PrP conformers (including the transmissible PrPSc form) that trigger downstream pathways leading to neuronal death. A mechanistic understanding of these diseases therefore requires knowledge of the quality control pathways that recognize and degrade aberrant PrPs. Here, we present comparative analyses of the biosynthesis, trafficking, and metabolism of a panel of genetic disease-causing prion protein mutants in the C-terminal domain. Using quantitative imaging and biochemistry, we identify a misfolded subpopulation of each mutant PrP characterized by relative detergent insolubility, inaccessibility to the cell surface, and incomplete glycan modifications. The misfolded populations of mutant PrPs were neither recognized by ER quality control pathways nor routed to ER-associated degradation despite demonstrable misfolding in the ER. Instead, mutant PrPs trafficked to the Golgi, from where the misfolded subpopulation was selectively trafficked for degradation in acidic compartments. Surprisingly, selective re-routing was dependent not only on a mutant globular domain, but on an additional lysine-based motif in the highly conserved unstructured N-terminus. These results define a specific trafficking and degradation pathway shared by many disease-causing PrP mutants. As the acidic lysosomal environment has been implicated in facilitating the conversion of PrPC to PrPSc, our identification of a mutant-selective trafficking pathway to this compartment may provide a cell biological basis for spontaneous generation of PrPSc in familial prion disease

    Formyl Peptide Receptor as a Novel Therapeutic Target for Anxiety-Related Disorders

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    Formyl peptide receptors (FPR) belong to a family of sensors of the immune system that detect microbe-associated molecules and inform various cellular and sensorial mechanisms to the presence of pathogens in the host. Here we demonstrate that Fpr2/3-deficient mice show a distinct profile of behaviour characterised by reduced anxiety in the marble burying and light-dark box paradigms, increased exploratory behaviour in an open-field, together with superior performance on a novel object recognition test. Pharmacological blockade with a formyl peptide receptor antagonist, Boc2, in wild type mice reproduced most of the behavioural changes observed in the Fpr2/3(-/-) mice, including a significant improvement in novel object discrimination and reduced anxiety in a light/dark shuttle test. These effects were associated with reduced FPR signalling in the gut as shown by the significant reduction in the levels of p-p38. Collectively, these findings suggest that homeostatic FPR signalling exerts a modulatory effect on anxiety-like behaviours. These findings thus suggest that therapies targeting FPRs may be a novel approach to ameliorate behavioural abnormalities present in neuropsychiatric disorders at the cognitive-emotional interface

    The Importance of Incorporating At-Home Testing Into SARS-CoV-2 Point Prevalence Estimates: Findings From a US National Cohort, February 2022

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    Background: Passive, case-based surveillance underestimates the true extent of active infections in the population due to undiagnosed and untested cases, the exclusion of probable cases diagnosed point-of-care rapid antigen tests, and the exclusive use of at-home rapid tests which are not reported as part of case-based surveillance. The extent in which COVID-19 surveillance may be underestimating the burden of infection is likely due to time-varying factors such as decreased test-seeking behaviors and increased access to and availability of at-home testing. Objective: The objective of this study is to estimate the prevalence of SARS-CoV-2 based on different definitions of a case to ascertain the extent to which cases of SARS-CoV-2 may be underestimated by case-based surveillance. Methods: A survey on COVID-19 exposure, infection, and testing was administered to calculate point prevalence of SARS-CoV-2 among a diverse sample of cohort adults from February 8, 2022, to February 22, 2022. Three-point prevalence estimates were calculated among the cohort, as follows: (1) proportion positives based on polymerase chain reaction (PCR) and rapid antigen tests; (2) proportion positives based on testing exclusively with rapid at-home tests; and (3) proportion of probable undiagnosed cases. Test positivity and prevalence differences across booster status were also examined. Results: Among a cohort of 4328, there were a total of 644 (14.9%) cases. The point prevalence estimate based on PCR or rapid antigen tests was 5.5% (95% CI 4.8%-6.2%), 3.7% (95% CI 3.1%-4.2%) based on at-home rapid tests, and 5.7% (95% CI 5.0%-6.4%) based on the case definition of a probable case. The total point prevalence across all definitions was 14.9% (95% CI 13.8%-16.0%). The percent positivity among PCR or rapid tests was 50.2%. No statistically significant differences were observed in prevalence between participants with a COVID-19 booster compared to fully vaccinated and nonboosted participants except among exclusive at-home rapid testers. Conclusions: Our findings suggest a substantial number of cases were missed by case-based surveillance systems during the Omicron B.1.1.529 surge, when at-home testing was common. Point prevalence surveys may be a rapid tool to be used to understand SARS-CoV-2 prevalence and would be especially important during case surges to measure the scope and spread of active infections in the population
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