294 research outputs found
Regulation of Zn and Fe transporters by the GPC1 gene during early wheat monocarpic senescence
BACKGROUND: During wheat senescence, leaf components are degraded in a coordinated manner, releasing amino acids and micronutrients which are subsequently transported to the developing grain. We have previously shown that the simultaneous downregulation of Grain Protein Content (GPC) transcription factors, GPC1 and GPC2, greatly delays senescence and disrupts nutrient remobilization, and therefore provide a valuable entry point to identify genes involved in micronutrient transport to the wheat grain.
RESULTS: We generated loss-of-function mutations for GPC1 and GPC2 in tetraploid wheat and showed in field trials that gpc1 mutants exhibit significant delays in senescence and reductions in grain Zn and Fe content, but that mutations in GPC2 had no significant effect on these traits. An RNA-seq study of these mutants at different time points showed a larger proportion of senescence-regulated genes among the GPC1 (64%) than among the GPC2 (37%) regulated genes. Combined, the two GPC genes regulate a subset (21.2%) of the senescence-regulated genes, 76.1% of which are upregulated at 12 days after anthesis, before the appearance of any visible signs of senescence. Taken together, these results demonstrate that GPC1 is a key regulator of nutrient remobilization which acts predominantly during the early stages of senescence. Genes upregulated at this stage include transporters from the ZIP and YSL gene families, which facilitate Zn and Fe export from the cytoplasm to the phloem, and genes involved in the biosynthesis of chelators that facilitate the phloem-based transport of these nutrients to the grains.
CONCLUSIONS: This study provides an overview of the transport mechanisms activated in the wheat flag leaf during monocarpic senescence. It also identifies promising targets to improve nutrient remobilization to the wheat grain, which can help mitigate Zn and Fe deficiencies that afflict many regions of the developing world.Fil: Pearce, Stephen. University of California; Estados UnidosFil: Tabbita, Facundo. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Instituto Nacional de TecnologÃa Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Cantu, Dario. University of California; Estados UnidosFil: Buffalo, Vince. University of California; Estados UnidosFil: Avni, Raz. Tel Aviv University; IsraelFil: Vazquez Gross, Hans. University of California; Estados UnidosFil: Zhao, Rongrong. China Agricultural University; ChinaFil: Conley, Christopher J.. University of California; Estados UnidosFil: Distelfeld, Assaf. Faculty Of Life Sciences, Department Of Molecular Biolo;Fil: Dubcovsky, Jorge. University of California; Estados Unidos. Howard Hughes Medical Institute ; Estados Unidos. Gordon & Betty Moore Foundation Investigator; Estados Unido
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Intraperitoneal photodynamic therapy causes a capillary-leak syndrome.
BackgroundIn patients undergoing intraperitoneal (IP) photodynamic therapy (PDT), the combination of aggressive surgical debulking and light therapy causes an apparent systemic capillary-leak syndrome that necessitates significant intensive care unit (ICU) management after surgery.MethodsFrom May 1997 to May 2001, 65 patients underwent surgical debulking and PDT as part of an ongoing phase II trial for disseminated IP cancer. Perioperative data were reviewed retrospectively, and statistical analyses were performed to determine whether any identifiable factors were associated with the need for mechanical ventilation for longer than 1 day and with the occurrence of postoperative complications.ResultsForty-three women and 22 men (mean age, 49 years) were treated. Operative time averaged 9.8 hours, and mean estimated blood loss was 1450 mL. The mean crystalloid requirement for the first 48 hours after surgery was 29.3 L, and 49 patients required blood products. Twenty-four patients were intubated for longer than 24 hours, with a mean of 8.3 days for those intubated longer than 1 day. The median ICU stay was 4 days. Overall, 110 complications developed in 45 (69%) of the 65 patients. Significant complications included 6 patients with acute respiratory distress syndrome, 28 patients with infectious complications, and 4 patients with anastomotic complications. Statistical analyses revealed that surgery-related factors were significantly associated with these complication outcomes.ConclusionsPatients who undergo surgical debulking and IP PDT develop a significant capillary-leak syndrome after surgery that necessitates massive volume resuscitation, careful ICU monitoring, and, frequently, prolonged ventilatory support
Affective Experience, Desire, and Reasons for Action
What is the role of affective experience in explaining how our desires provide us with reasons for action? When we desire that p, we are thereby disposed to feel attracted to the prospect that p, or to feel averse to the prospect that not-p. In this paper, we argue that affective experiences – including feelings of attraction and aversion – provide us with reasons for action in virtue of their phenomenal character. Moreover, we argue that desires provide us with reasons for action only insofar as they are dispositions to have affective experiences. On this account, affective experience has a central role to play in explaining how desires provide reasons for action
Towards empathic neurofeedback for interactive storytelling
Interactive Narrative is a form of digital entertainment based on AI techniques which support narrative
generation and user interaction. Despite recent progress in the field, there is still a lack of unified models
integrating narrative generation, user response and interaction.
This paper addresses this issue by revisiting existing Interactive Narrative paradigms, granting explicit
status to users’ disposition towards story characters. We introduce a novel Brain-Computer Interface
(BCI) design, which attempts to capture empathy for the main character in a way that is compatible with
filmic theories of emotion.
Results from two experimental studies with a fully-implemented system demonstrate the effectiveness
of a neurofeedback-based approach, showing that subjects can successfully modulate their emotional
support for a character who is confronted with challenging situations. A preliminary fMRI analysis also
shows activation during user interaction, in regions of the brain associated with emotional control
Changes in Albuminuria Predict Cardiovascular and Renal Outcomes in Type 2 Diabetes: A Post Hoc Analysis of the LEADER Trial
OBJECTIVE A post hoc analysis to investigate the association between 1-year changes in albuminuria and subsequent risk of cardiovascular and renal events. RESEARCH DESIGN AND METHODS LEADER was a randomized trial of liraglutide up to 1.8 mg/day versus placebo added to standard care for 3.5-5 years in 9,340 participants with type 2 diabetes and high cardiovascular risk. We calculated change in urinary albumin-to-creatinine ratio (UACR) from baseline to 1 year in participants with >30% reduction (n = 2,928), 30-0% reduction (n = 1,218), or any increase in UACR (n = 4,124), irrespective of treatment. Using Cox regression, risks of major adverse cardiovascular events (MACE) and a composite nephropathy outcome (from 1 year to end of trial in subgroups by baseline UACR [= 300 mg/g]) were assessed. The analysis was adjusted for treatment allocation alone as a fixed factor and for baseline variables associated with cardiovascular and renal outcomes. RESULTS For MACE, hazard ratios (HRs) for those with >30% and 30-0% UACR reduction were 0.82 (95% CI 0.71, 0.94; P = 0.006) and 0.99 (0.82, 1.19; P = 0.912), respectively, compared with any increase in UACR (reference). For the composite nephropathy outcome, respective HRs were 0.67 (0.49, 0.93; P = 0.02) and 0.97 (0.66, 1.43; P = 0.881). Results were independent of baseline UACR and consistent in both treatment groups. After adjustment, HRs were significant and consistent in >30% reduction subgroups with baseline micro- or macroalbuminuria. CONCLUSIONS A reduction in albuminuria during the 1st year was associated with fewer cardiovascular and renal outcomes, independent of treatment. Albuminuria monitoring remains an important part of diabetes care, with great unused potential
Retrospective observational study to assess the clinical management and outcomes of hospitalised patients with complicated urinary tract infection in countries with high prevalence of multidrug resistant Gram-negative bacteria (RESCUING)
Introduction: the emergence of multidrug resistant (MDR) Gram-negative bacteria (GNB), including carbapenemase-producing strains, has become a major therapeutic challenge. These MDR isolates are often involved in complicated urinary tract infection (cUTI), and are associated with poor clinical outcomes. The study has been designed to gain insight into the epidemiology, clinical management, outcome and healthcare cost of patients with cUTI, especially in countries with high prevalence of MDR GNB. Methods and analysis: this multinational and multicentre observational, retrospective study will identify cases from 1 January 2013 to 31 December 2014 in order to collect data on patients with cUTI as a cause of hospital admission, and patients who develop cUTI during their hospital stay. The primary end point will be treatment failure defined as the presence of any of the following criteria: (1) signs or symptoms of cUTI present at diagnosis that have not improved by days 5-7 with appropriate antibiotic therapy, (2) new cUTI-related symptoms that have developed within 30 days of diagnosis, (3) urine culture taken within 30 days of diagnosis, either during or after completion of therapy, that grows ≥10(4) colony-forming unit/mL of the original pathogen and (4) death irrespective of cause within 30 days of the cUTI diagnosis. Sample size: 1000 patients afford a power of 0.83 (α=0.05) to detect an absolute difference of 10% in the treatment failure rate between MDR bacteria and other pathogens. This should allow for the introduction of about 20 independent risk factors (or their interaction) in a logistic regression model looking at risk factors for failure. Ethics and dissemination: approval will be sought from all relevant Research Ethics Committees. Publication of this study will be considered as a joint publication by the participating investigator leads, and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE)
Cardiovascular and renal outcomes by baseline albuminuria status and renal function — results from the LEADER randomized trial
Aim: To assess cardiorenal outcomes by baseline urinary albumin-to-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) in the contemporary LEADER cohort. Materials and methods: LEADER was a multinational, double-blind trial. Patients with type 2 diabetes and high cardiovascular (CV) risk were randomized 1:1 to the glucagon-like peptide-1 analogue liraglutide (≤1.8 mg daily; n = 4668) or placebo (n = 4672) plus standard care and followed for 3.5 to 5 years. Primary composite outcomes were time to first non-fatal myocardial infarction, non-fatal stroke or CV death. Post hoc Cox regression analyses of outcomes by baseline UACR and eGFR subgroups were conducted with adjustment for baseline variables. Results: In the LEADER population, 1598 (17.5%), 2917 (31.9%), 1200 (13.1%), 1611 (17.6%), 845 (9.2%) and 966 (10.6%) had UACR = 0, >0 to <15, 15 to <30, 30 to <100, 100 to <300 and ≥300 mg/g, respectively. Increasing UACR and decreasing eGFR were linked with higher risks of the primary outcome, heart failure hospitalization, a composite renal outcome and death (P-values for the Cochran-Armitage test for trends were all <.0001). Across UACR and eGFR subgroups, risks of cardiorenal events and death were generally lower or similar with liraglutide versus placebo. Conclusions: In a contemporary type 2 diabetes population, increasing baseline UACR and declining eGFR were linked with higher risks of cardiorenal events and death
Effect of Dapagliflozin on Cardiovascular Outcomes According to Baseline Kidney Function and Albuminuria Status in Patients With Type 2 Diabetes A Prespecified Secondary Analysis of a Randomized Clinical Trial
ImportanceSodium-glucose cotransporter 2 inhibitors, such as dapagliflozin, promote renal glucose excretion and reduce cardiovascular (CV) deaths and hospitalizations for heart failure (HHF) among patients with type 2 diabetes. The relative CV efficacy and safety of dapagliflozin according to baseline kidney function and albuminuria status are unknown.ObjectiveTo assess the CV efficacy and safety of dapagliflozin according to baseline estimated glomerular filtration rate (eGFR) and urinary albumin to creatinine ratio (UACR).Design, setting, and participantsThis secondary analysis of the randomized clinical trial Dapagliflozin Effect on Cardiovascular Events-Thrombolysis in Myocardial Infarction 58 compared dapagliflozin vs placebo in 17 160 patients with type 2 diabetes and a baseline creatinine clearance of 60 mL/min or higher. Patients were categorized according to prespecified subgroups of baseline eGFR (InterventionsDapagliflozin vs placebo.Main outcomes and measuresThe dual primary end points were major adverse cardiovascular events (myocardial infarction, stroke, and CV death) and the composite of CV death or HHF.ResultsAt baseline, 1265 patients (7.4%) had an eGFR below 60 mL/min/1.73 m2, and 5199 patients (30.9%) had albuminuria. Among patients having data for both eGFR and UACR, 10 958 patients (65.1%) had an eGFR equal to or higher than 60 mL/min/1.73 m2 and an UACR below 30 mg/g (mean [SD] age, 63.7 [6.7] years; 40.1% women), 5336 patients (31.7%) had either an eGFR below 60 mL/min/1.73 m2 or albuminuria (mean [SD] age, 64.1 [7.1] years; 32.6% women), and 548 patients (3.3%) had both (mean [SD] age, 66.8 [6.9] years; 30.5% women). In the placebo group, patients with more CKD markers had higher event rates at 4 years as assessed using the Kaplan-Meier approach for the composite of CV death or HHF (3.9% for 0 markers, 8.3% for 1 marker, and 17.4% for 2 markers) and major adverse cardiovascular events (7.5% for 0 markers, 11.6% for 1 marker, and 18.9% for 2 markers). Estimates for relative risk reductions for the composite of CV death or HHF and for major adverse cardiovascular events were generally consistent across subgroups (both P > .24 for interaction), although greater absolute risk reductions were observed with more markers of CKD. The absolute risk difference for the composite of CV death or HHF was greater for patients with more markers of CKD (0 markers, -0.5%; 1 marker, -1.0%; and 2 markers, -8.3%; P = .02 for interaction). The numbers of amputations, cases of diabetic ketoacidosis, fractures, and major hypoglycemic events were balanced or numerically lower with dapagliflozin compared with placebo for patients with an eGFR below 60 mL/min/1.73 m2 and an UACR of 30 mg/g or higher.Conclusions and relevanceThe effect of dapagliflozin on the relative risk for CV events was consistent across eGFR and UACR groups, with the greatest absolute benefit for the composite of CV death or HHF observed among patients with both reduced eGFR and albuminuria.Trial registrationClinicalTrials.gov Identifier: NCT01730534
Sodium-Glucose Cotransporter 2 Inhibitors and Risk of Hyperkalemia in People With Type 2 Diabetes: A Meta-Analysis of Individual Participant Data From Randomized, Controlled Trials
Background: Hyperkalemia increases risk of cardiac arrhythmias and death and limits the use of renin-angiotensin-aldosterone system (RAAS) inhibitors and mineralocorticoid receptor antagonists (MRAs), which improve clinical outcomes in people with chronic kidney disease (CKD) and/or systolic heart failure. Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of cardiorenal events in people with type 2 diabetes at high cardiovascular risk or with CKD. However, their effect on hyperkalemia has not been systematically evaluated. / Methods: A meta-analysis was conducted using individual participant data from randomized, double-blind, placebo-controlled clinical outcome trials with SGLT2 inhibitors in people with type 2 diabetes at high cardiovascular risk and/or with CKD, in which serum potassium levels were routinely measured. The primary outcome was time to serious hyperkalemia, defined as central laboratory determine serum potassium ≥6.0 mmol/L, with other outcomes including investigator-reported hyperkalemia events and hypokalemia (serum potassium ≤3.5 mmol/L). Cox regression analyses were performed to estimate treatment effects from each trial with hazards ratios (HR) and corresponding 95% CI pooled using random effects models to obtain summary treatment effects, overall and across key subgroups. / Results: Results from six trials were included comprising 49,875 participants assessing four SGLT2 inhibitors. 1,754 participants developed serious hyperkalemia and an additional 1,119 investigator-reported hyperkalemia events were recorded. SGLT2 inhibitors reduced the risk of serious hyperkalemia (HR 0.84, 95% CI 0.76-0.93), an effect consistent across studies (P-heterogeneity=0.71). The incidence of investigator-reported hyperkalemia was also lower with SGLT2 inhibitors (HR 0.80, 95% CI 0.68-0.93; P-heterogeneity=0.21). Reductions in serious hyperkalemia were observed across a range of subgroups including baseline kidney function, history of heart failure, RAAS inhibitor, diuretic and MRA use. SGLT2 inhibitors did not increase the risk of hypokalemia (HR 1.04, 95% CI 0.94-1.15; P-heterogeneity=0.42). / Conclusions: SGLT2 inhibitors reduce the risk of serious hyperkalemia in people with type 2 diabetes at high cardiovascular risk and/or with CKD, without increasing the risk of hypokalemia
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