1,771 research outputs found
Completion problems for real matrices, II
Thirty years ago, G.N. de Oliveira has proposed the following completion problems: Describe the possible characteristic polynomials of [C-ij], i,j is an element of {1, 2}, where C-1,C-1 and C-2,C-2 are square submatrices, when some of the blocks C-ij are fixed and the others vary. Several of these problems remain unsolved. This paper gives the solution, over the field of real numbers, of Oliveira's problem where the blocks C-1,C-1, C-2,C-2 are fixed and the others vary
Nanoencapsulation of bovine lactoferrin for oral hygiene applications
info:eu-repo/semantics/publishedVersio
Evidence of Strong Guest–Host Interactions in Simvastatin Loaded in Mesoporous Silica MCM-41
Funding Information: This research was funded by the Associate Laboratory for Green Chemistry LAQV, which is financed by national funds from FCT/MEC (UID/QUI/50006/2019) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER—007265). This research was funded by the Interreg 2 Seas program 2014–2020, and co-funded by the European Regional Development Fund (FEDER) under subsidy contract 2S01-059_IMODE and 2S07-033_ Site Drug. This research was funded by the Program PHC PESSOA 2018 project nbr 4340/40868R. This research was funded by National Funds through FCT—Portuguese Foundation for Science and Technology, reference UIDB/00100/2020, UIDP/00100/2020, LA/P/0056/2020, UIDB/50025/2020-2023, and PTNMR (ROTEIRO/0031/2013; PINFRA/22161/2016), co-financed by ERDF through COMPETE 2020, Portugal, POCI and PORL and FCT through PIDDAC (POCI-01-0145-FEDER-007688). M.C.C. acknowledges PTNMR&i3N for the researcher contract. T. Cordeiro acknowledges Fundação para a Ciência e a Tecnologia (FCT) for the scholarship SFRH/BD/114653/2016. I. Matos acknowledges FCT for the Investigator FCT contract IF/01242/2014/CP1224/CT0008. Publisher Copyright: © 2023 by the authors.A rational design of drug delivery systems requires in-depth knowledge not only of the drug itself, in terms of physical state and molecular mobility, but also of how it is distributed among a carrier and its interactions with the host matrix. In this context, this work reports the behavior of simvastatin (SIM) loaded in mesoporous silica MCM-41 matrix (average pore diameter ~3.5 nm) accessed by a set of experimental techniques, evidencing that it exists in an amorphous state (X-ray diffraction, ssNMR, ATR-FTIR, and DSC). The most significant fraction of SIM molecules corresponds to a high thermal resistant population, as shown by thermogravimetry, and which interacts strongly with the MCM silanol groups, as revealed by ATR-FTIR analysis. These findings are supported by Molecular Dynamics (MD) simulations predicting that SIM molecules anchor to the inner pore wall through multiple hydrogen bonds. This anchored molecular fraction lacks a calorimetric and dielectric signature corresponding to a dynamically rigid population. Furthermore, differential scanning calorimetry showed a weak glass transition that is shifted to lower temperatures compared to bulk amorphous SIM. This accelerated molecular population is coherent with an in-pore fraction of molecules distinct from bulklike SIM, as highlighted by MD simulations. MCM-41 loading proved to be a suitable strategy for a long-term stabilization (at least three years) of simvastatin in the amorphous form, whose unanchored population releases at a much higher rate compared to the crystalline drug dissolution. Oppositely, the surface-attached molecules are kept entrapped inside pores even after long-term release assays.publishersversionpublishe
70-Gene Signature as an Aid to Treatment Decisions in Early-Stage Breast Cancer.
The 70-gene signature test (MammaPrint) has been shown to improve prediction of clinical outcome in women with early-stage breast cancer. We sought to provide prospective evidence of the clinical utility of the addition of the 70-gene signature to standard clinical-pathological criteria in selecting patients for adjuvant chemotherapy.
In this randomized, phase 3 study, we enrolled 6693 women with early-stage breast cancer and determined their genomic risk (using the 70-gene signature) and their clinical risk (using a modified version of Adjuvant! Online). Women at low clinical and genomic risk did not receive chemotherapy, whereas those at high clinical and genomic risk did receive such therapy. In patients with discordant risk results, either the genomic risk or the clinical risk was used to determine the use of chemotherapy. The primary goal was to assess whether, among patients with high-risk clinical features and a low-risk gene-expression profile who did not receive chemotherapy, the lower boundary of the 95% confidence interval for the rate of 5-year survival without distant metastasis would be 92% (i.e., the noninferiority boundary) or higher.
A total of 1550 patients (23.2%) were deemed to be at high clinical risk and low genomic risk. At 5 years, the rate of survival without distant metastasis in this group was 94.7% (95% confidence interval, 92.5 to 96.2) among those not receiving chemotherapy. The absolute difference in this survival rate between these patients and those who received chemotherapy was 1.5 percentage points, with the rate being lower without chemotherapy. Similar rates of survival without distant metastasis were reported in the subgroup of patients who had estrogen-receptor-positive, human epidermal growth factor receptor 2-negative, and either node-negative or node-positive disease.
Among women with early-stage breast cancer who were at high clinical risk and low genomic risk for recurrence, the receipt of no chemotherapy on the basis of the 70-gene signature led to a 5-year rate of survival without distant metastasis that was 1.5 percentage points lower than the rate with chemotherapy. Given these findings, approximately 46% of women with breast cancer who are at high clinical risk might not require chemotherapy. (Funded by the European Commission Sixth Framework Program and others; ClinicalTrials.gov number, NCT00433589; EudraCT number, 2005-002625-31.)
Depth of Response in Multiple Myeloma: A Pooled Analysis of Three PETHEMA/GEM Clinical Trials
[EN] Purpose—To perform a critical analysis on the impact of depth of response in newly diagnosed multiple myeloma (MM).
Patients and Methods—Data were analyzed from 609 patients who were enrolled in the GEM (Grupo Español de Mieloma) 2000 and GEM2005MENOS65 studies for transplant-eligible MM and the GEM2010MAS65 clinical trial for elderly patients with MM who had minimal residual disease (MRD) assessments 9 months after study enrollment. Median follow-up of the series was 71 months.
Results—Achievement of complete remission (CR) in the absence of MRD negativity was not associated with prolonged progression-free survival (PFS) and overall survival (OS) compared with near-CR or partial response (median PFS, 27, 27, and 29 months, respectively; median OS, 59, 64, and 65 months, respectively). MRD-negative status was strongly associated with prolonged PFS (median, 63 months; P < .001) and OS (median not reached; P < .001) overall and in subgroups defined by prior transplantation, disease stage, and cytogenetics, with prognostic superiority of MRD negativity versus CR particularly evident in patients with high-risk cytogenetics. Accordingly, Harrell C statistics showed higher discrimination for both PFS and OS in Cox models that included MRD (as opposed to CR) for response assessment. Superior MRD-negative rates after different induction regimens anticipated prolonged PFS. Among 34 MRD-negative patients with MM and a phenotypic pattern of bone marrow involvement similar to monoclonal gammopathy of undetermined significance at diagnosis, the probability of “operational cure” was high; median PFS was 12 years, and the 10-year OS rate was 94%.
Conclusion—Our results demonstrate that MRD-negative status surpasses the prognostic value of CR achievement for PFS and OS across the disease spectrum, regardless of the type of treatment or patient risk group. MRD negativity should be considered as one of the most relevant end points for transplant-eligible and elderly fit patients with MM
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
Financial feasibility of end-user designed rainwater harvesting and greywater reuse systems for high water use households
© 2017, The Author(s). Water availability pressures, competing end-uses and sewers at capacity are all drivers for change in urban water management. Rainwater harvesting (RWH) and greywater reuse (GWR) systems constitute alternatives to reduce drinking water usage and in the case of RWH, reduce roof runoff entering sewers. Despite the increasing popularity of installations in commercial buildings, RWH and GWR technologies at a household scale have proved less popular, across a range of global contexts. For systems designed from the top-down, this is often due to the lack of a favourable cost-benefit (where subsidies are unavailable), though few studies have focused on performing full capital and operational financial assessments, particularly in high water consumption households. Using a bottom-up design approach, based on a questionnaire survey with 35 households in a residential complex in Bucaramanga, Colombia, this article considers the initial financial feasibility of three RWH and GWR system configurations proposed for high water using households (equivalent to >203L per capita per day). A full capital and operational financial assessment was performed at a more detailed level for the most viable design using historic rainfall data. For the selected configuration (‘Alt 2’), the estimated potable water saving was 44% (equivalent to 131m3/year) with a rate of return on investment of 6.5% and an estimated payback period of 23years. As an initial end-user-driven design exercise, these results are promising and constitute a starting point for facilitating such approaches to urban water management at the household scale
Potential of FX06 to prevent disease progression in hospitalized non-intubated COVID-19 patients — the randomized, EU-wide, placebo-controlled, phase II study design of IXION
Background: More than 2.7 million hospitalizations of COVID-19-infected patients have occurred in Europe alone since the outbreak of the coronavirus in 2020. Interventions against SARS-CoV-2 are still in high need to prevent admissions to ICUs worldwide. FX06, a naturally occurring peptide in humans and other mammals, has the potential to reduce capillary leak by improving endothelial dysfunction and thus preventing the deterioration of patients. With IXION, we want to investigate the potential of FX06 to prevent disease progression in hospitalized, non-intubated COVID-19 patients. Methods: IXION is an EU-wide, multicentre, placebo-controlled, double-blinded, parallel, randomized (2:1) phase II clinical study. Patient recruitment will start in September 2022 (to Q2/2023) in Germany, Italy, Lithuania, Spain, Romania, Portugal, and France. A total of 306 hospitalized patients (>= 18 years and < 75 years) with a positive SARS-CoV-2 PCR test and a COVID-19 severity of 4-6 according to the WHO scale will be enrolled. After randomization to FX06 or placebo, patients will be assessed until day 28 (and followed up until day 60). FX06 (2 x 200 mg per day) or placebo will be administered intravenously for 5 consecutive days. The primary endpoint is to demonstrate a difference in the proportion of patients with progressed/worsened disease state in patients receiving FX06 compared to patients receiving placebo. Secondary endpoints are lung function, oxygen saturation and breathing rate, systemic inflammation, survival, capillary refill time, duration of hospital stay, and drug accountability. Discussion: With IXION, the multidisciplinary consortium aims to deliver a new therapy in addition to standard care against SARS-CoV-2 for the clinical management of COVID-19 during mild and moderate stages. Potential limitations might refer to a lack of recruiting and drop-out due to various possible protocol violations. While we controlled for drop-outs in the same size estimation, recruitment problems may be subject to external problems difficult to control for
How genomics can help biodiversity conservation
The availability of public genomic resources can greatly assist biodiversity assessment, conservation, and restoration efforts by providing evidence for scientifically informed management decisions. Here we survey the main approaches and applications in biodiversity and conservation genomics, considering practical factors, such as cost, time, prerequisite skills, and current shortcomings of applications. Most approaches perform best in combination with reference genomes from the target species or closely related species. We review case studies to illustrate how reference genomes can facilitate biodiversity research and conservation across the tree of life. We conclude that the time is ripe to view reference genomes as fundamental resources and to integrate their use as a best practice in conservation genomics.info:eu-repo/semantics/publishedVersio
The era of reference genomes in conservation genomics
Progress in genome sequencing
now enables the large-scale
generation of reference genomes.
Various international initiatives
aim to generate reference genomes
representing global biodiversity.
These genomes provide
unique insights into genomic diversity
and architecture, thereby enabling
comprehensive analyses
of population and functional
genomics, and are expected
to revolutionize conservation
genomics
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