13 research outputs found
Interaction between multi components vortices at arbitrary distances using a variational method in the Ginzburg-Landau theory
We study the interaction between the vortices in multi components
superconductors based on the Jacobs and Rebbi variation method using
Ginzburg-Landau theory. With one condensation, we get attraction interaction
between the vortices for type I and repulsion for type II superconductors. With
two condensation states such as Mg B_{2} superconductors the behavior is quite
different. There is attraction at large distances and repulsion when the
vortices are close to each other. A stability point at distance
2.7/{\lambda}_{1} is obtained. In the case of three condensation states such as
iron based superconductors,we see different behavior depending on penetration
depth and correlation length. The formation energy of a vortex with three
condensation states is larger than the one with one condensation state with
comparable penetration and correlation length. We obtain two stability points
for the superconductors with three condensation states
Quark Confinement in Restricted SU(2) Gauge Theory
We apply Zwanziger formalism to Cho restricted theory to obtain the
potential in a static quark-antiquark pair. Cho restricted theory is a
self-consistent subset of a non-Abelian gauge theory which tries to
describe the infrared regime of Yang-Mills gauge theories. In Zwanziger
formalism, a local Lagrangian depending on two electric and magnetic gauge
fields is constructed for the theories where both electric and magnetic charges
exist. Based on this local Lagrangian the propagator and then the potential
between quarks is calculated in two limits: and , where is the mass of the dual gauge boson and is the
distance between the quark and the antiquark.Comment: 2 Figures, 15 pages, Version accepted for publication in PR
Decreased serum levels of angiotensin converting enzyme (ACE)2 and enhanced cytokine levels with severity of COVID-19: normalisation upon disease recovery
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). Circulating soluble angiotensin-converting enzyme (sACE2)2, the main receptor for SARS-CoV-2, together with components of the renin-angiotensin system promote infection and disease severity. Objective This pilot study followed the time-course of sACE2 levels in relation to systemic cytokines in severe and moderate COVID-19 patients treated with remdesivir/dexamethasone in combination. Methods Peripheral blood was obtained upon admission from 30 patients (12 with moderate disease and 18 with severe disease) and 14 patients with PCR-confirmed mild COVID-19. Severe and moderate patients were treated with remdesivir (200mg/first day and 100mg/day for the remaining days) and dexamethasone (100mg/day). 6 healthy control subjects (HC) were also enrolled. Serum interleukin (IL)-6 and IL-8 and sACE2 levels were measured by ELISA at baseline and during treatment in severe and moderate patients and at baseline in mild and HCs. Results Baseline sACE2 levels were lower in severe (p = 0.0005) and moderate (p = 0.0022) patients than in patients with mild COVID-19 and in HC (p = 0.0023 and p = 0.0012 respectively). Treatment significantly increased sACE2 levels in patients with moderate disease (p = 0.0156) but only 50% of patients with severe disease showed enhanced levels compared to baseline. Systemic IL-6 and IL-8 levels were higher in all patient groups compared with HC and were not significantly affected over time or by remdesivir/dexamethasone treatment for 5 days. Conclusion Serum sACE2 levels increase in severe COVID-19 patients as they recover over time whilst circulating cytokines are unaffected. Future studies should link these results to clinical outcomes
Intermediate versus standard-dose prophylactic anticoagulation and statin therapy versus placebo in critically-ill patients with COVID-19: Rationale and design of the INSPIRATION/INSPIRATION-S studies
Background: Microvascular and macrovascular thrombotic events are among the hallmarks of coronavirus disease 2019 (COVID-19). Furthermore, the exuberant immune response is considered an important driver of pulmonary and extrapulmonary manifestations of COVID-19. The optimal management strategy to prevent thrombosis in critically-ill patients with COVID-19 remains unknown. Methods: The Intermediate versus Standard-dose Prophylactic anticoagulation In cRitically-ill pATIents with COVID-19: An opeN label randomized controlled trial (INSPIRATION) and INSPIRATION-statin (INSPIRATION-S) studies test two independent hypotheses within a randomized controlled trial with 2 � 2 factorial design. Hospitalized critically-ill patients with reverse transcription polymerase chain reaction confirmed COVID-19 will be randomized to intermediate-dose versus standard dose prophylactic anticoagulation. The 600 patients undergoing this randomization will be screened and if meeting the eligibility criteria, will undergo an additional double-blind stratified randomization to atorvastatin 20 mg daily versus matching placebo. The primary endpoint, for both hypotheses will be tested for superiority and includes a composite of adjudicated acute arterial thrombosis, venous thromboembolism (VTE), use of extracorporeal membrane oxygenation, or all-cause death within 30 days from enrollment. Key secondary endpoints include all-cause mortality, adjudicated VTE, and ventilator-free days. Key safety endpoints include major bleeding according to the Bleeding Academic Research Consortium definition and severe thrombocytopenia (platelet count 3 times upper normal limit and clinically-diagnosed myopathy. The primary analyses will be performed in the modified intention-to-treat population. Results will be tested in exploratory analyses across key subgroups and in the intention-to-treat and per-protocol cohorts. Conclusions: INSPIRATION and INSPIRATON-S studies will help address clinically-relevant questions for antithrombotic therapy and thromboinflammatory therapy in critically-ill patients with COVID-19. © 2020 Elsevier Lt
Atorvastatin versus placebo in ICU patients with COVID-19: ninety-day results of the INSPIRATION-S trial
Background In the INSPIRATION-S trial, atorvastatin versus placebo was associated with a nonsignificant 16% reduction in 30-day composite of venous/arterial thrombosis or death in intensive care unit (ICU) patients with COVID-19. Thrombo-inflammatory response in coronavirus disease 2019 (COVID-19) may last beyond the first 30 days.Methods This article reports the effects of atorvastatin 20 mg daily versus placebo on 90-day clinical and functional outcomes from INSPIRATION-S, a double-blind multicenter randomized trial of adult ICU patients with COVID-19. The main outcome for this prespecified study was a composite of adjudicated venous/arterial thrombosis, treatment with extracorporeal membrane oxygenation (ECMO), or all-cause mortality. Functional status was assessed with the Post-COVID-19 Functional Scale.Results In the primary analysis, 587 patients were included (age: 57 [Q1–Q3: 45–68] years; 44% women). By 90-day follow-up, the main outcome occurred in 96 (33.1%) patients assigned to atorvastatin and 113 (38.0%) assigned to placebo (hazard ratio [HR]: 0.80, 95% confidence interval [CI]: 0.60–1.05, p = 0.11). Atorvastatin in patients who presented within 7 days of symptom onset was associated with reduced 90-day hazard for the main outcome (HR: 0.60, 95% CI: 0.42–0.86, p interaction = 0.02). Atorvastatin use was associated with improved 90-day functional status, although the upper bound CI crossed 1.0 (ORordinal: 0.64, 95% CI: 0.41–1.01, p = 0.05).Conclusion Atorvastatin 20 mg compared with placebo did not significantly reduce the 90-day composite of death, treatment with ECMO, or venous/arterial thrombosis. However, the point estimates do not exclude a potential clinically meaningful treatment effect, especially among patients who presented within 7 days of symptom onset (NCT04486508).Thrombosis and Hemostasi
Effect of Intermediate-Dose vs Standard-Dose Prophylactic Anticoagulation on Thrombotic Events, Extracorporeal Membrane Oxygenation Treatment, or Mortality among Patients with COVID-19 Admitted to the Intensive Care Unit: The INSPIRATION Randomized Clinical Trial
Importance: Thrombotic events are commonly reported in critically ill patients with COVID-19. Limited data exist to guide the intensity of antithrombotic prophylaxis. Objective: To evaluate the effects of intermediate-dose vs standard-dose prophylactic anticoagulation among patients with COVID-19 admitted to the intensive care unit (ICU). Design, Setting, and Participants: Multicenter randomized trial with a 2 � 2 factorial design performed in 10 academic centers in Iran comparing intermediate-dose vs standard-dose prophylactic anticoagulation (first hypothesis) and statin therapy vs matching placebo (second hypothesis; not reported in this article) among adult patients admitted to the ICU with COVID-19. Patients were recruited between July 29, 2020, and November 19, 2020. The final follow-up date for the 30-day primary outcome was December 19, 2020. Interventions: Intermediate-dose (enoxaparin, 1 mg/kg daily) (n = 276) vs standard prophylactic anticoagulation (enoxaparin, 40 mg daily) (n = 286), with modification according to body weight and creatinine clearance. The assigned treatments were planned to be continued until completion of 30-day follow-up. Main Outcomes and Measures: The primary efficacy outcome was a composite of venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation, or mortality within 30 days, assessed in randomized patients who met the eligibility criteria and received at least 1 dose of the assigned treatment. Prespecified safety outcomes included major bleeding according to the Bleeding Academic Research Consortium (type 3 or 5 definition), powered for noninferiority (a noninferiority margin of 1.8 based on odds ratio), and severe thrombocytopenia (platelet count <20 �103/µL). All outcomes were blindly adjudicated. Results: Among 600 randomized patients, 562 (93.7) were included in the primary analysis (median interquartile range age, 62 50-71 years; 237 42.2% women). The primary efficacy outcome occurred in 126 patients (45.7%) in the intermediate-dose group and 126 patients (44.1%) in the standard-dose prophylaxis group (absolute risk difference, 1.5% 95% CI,-6.6% to 9.8%; odds ratio, 1.06 95% CI, 0.76-1.48; P =.70). Major bleeding occurred in 7 patients (2.5%) in the intermediate-dose group and 4 patients (1.4%) in the standard-dose prophylaxis group (risk difference, 1.1% 1-sided 97.5% CI,-� to 3.4%; odds ratio, 1.83 1-sided 97.5% CI, 0.00-5.93), not meeting the noninferiority criteria (P for noninferiority >.99). Severe thrombocytopenia occurred only in patients assigned to the intermediate-dose group (6 vs 0 patients; risk difference, 2.2% 95% CI, 0.4%-3.8%; P =.01). Conclusions and Relevance: Among patients admitted to the ICU with COVID-19, intermediate-dose prophylactic anticoagulation, compared with standard-dose prophylactic anticoagulation, did not result in a significant difference in the primary outcome of a composite of adjudicated venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation, or mortality within 30 days. These results do not support the routine empirical use of intermediate-dose prophylactic anticoagulation in unselected patients admitted to the ICU with COVID-19. Trial Registration: ClinicalTrials.gov Identifier: NCT04486508. © 2021 American Medical Association. All rights reserved
The Relationship Between Postnatal Hypoglycemia and Umbilical Artery Doppler Ultrasonography in Neonates with Intrauterine Growth Restriction: A Longitudinal Follow-up Study
Background: Intrauterine growth restriction (IUGR) refers to fetuses with an estimated ultrasonography weight below the 10% percentile. Hypoglycemia is a major concern in neonates with IUGR.
Objective: To investigate the relationship between umbilical artery (UA) Doppler ultrasonography and neonate hypoglycemia and IUGR.
Materials and Methods: This was a longitudinal follow-up study consisting of 114 neonates (gestational age of 28-40 wk) born with IUGR in the third trimester of pregnancy at Shahid Sadoughi Hospital, Yazd, Iran between May 2016 and October 2017. The neonates were assigned into three subgroups of normal UA Doppler, absent end-diastolic flow (EDF) in UA Doppler, and reverse EDF in UA Doppler. The blood glucose of the neonates was checked one, two, three, six, 12, 24 and 48 hr after birth, and the neonates were placed in the hypoglycemia or euglycemia groups according to guidelines.
Results: Out of the 114 neonates included in the study, 75 (65.8%) had normal UA Doppler, 29 (25.4%) had absent EDF in UA Doppler, and 10 (8.8%) had reverse EDF in UA Doppler. There was a significant difference in the mean blood glucose in the first hr between the normal UA Doppler group and the reverse EDF in UA Doppler group (p lt; 0.01).
Conclusion: Postnatal hypoglycemia in neonates with IUGR is associated with the result of UA Doppler ultrasonography during pregnancy.
Key words: Growth restriction, Hypoglycemia, Ultrasonography Doppler, Umbilical artery