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Gentry Forsyth posted an update 2 days, 10 hours ago
2% of COVID-19-related abstracts undergo a discrete change by the time of publication, but the majority of these changes do not qualitatively change the conclusions of the paper.Active Queue Management (AQM) is recommended by Internet Engineering Task Force to mitigate the bufferbloat phenomenon in the Internet. In this paper, we show the results of comprehensive measurements carried out in our university network, in which a device with an AQM algorithm, designed and programmed for this purpose, was running. The implemented AQM algorithm was based on the dropping function, i.e. arriving packets were dropped randomly, with the probability being a function of the queue length. Several different dropping function forms, proposed in the networking literature, were used, in addition to the classic FIFO queue (no AQM). The experiment lasted over a month, during which the state of the network was measured and recorded several thousand times. This made the results independent of the natural fluctuations of the users’ behavior and the network load. Conclusions on the general performance improvement offered by the implemented AQM, as well as the differences in the performance between particular forms of the dropping function, were reached. Some of these conclusions differ from those drawn previously from simulations. This underlines the need for carrying measurements of new AQMs in real, operating networks, with complex, natural traffic.Many anesthetics, including Propofol, have been reported to induce elevation of intracellular calcium, and we were interested to investigate the possible contribution of calcium elevation to the mechanism of the newly approved remimazolam actions. Remimazolam is an intravenous anesthetic first approved in Japan in July 2020, and is thought to exert its anesthetic actions via γ-aminobutyric acid A (GABAA) receptors; however, the precise mechanisms of how remimazolam elevates intracellular calcium levels remains unclear. We examined the remimazolam-induced elevation of intracellular calcium using SHSY-5Y neuroblastoma cells, COS-7 cells, HEK293 cells, HeLa cells, and human umbilical vein endothelial cells (HUVECs) loaded with fluorescent dyes for live imaging. We confirmed that high concentrations of remimazolam (greater than 300 μM) elevated intracellular calcium in a dose-dependent manner in these cells tested. This phenomenon was not influenced by elimination of extracellular calcium. CI-1040 mw The calcium elevation w further studies are required to identify which type of GPCRs is involved.
To investigate the characteristics of coronary artery bifurcation type (parallel or perpendicular type) using three-dimensional (3D) optical coherence tomography (OCT), and determine the feasibility, reproducibility, assessment time and correlation with bifurcation angles measured by 3D quantitative coronary angiography (QCA).
We evaluated 60 lesions at the coronary bifurcation that were treated by main vessel (MV) stenting with kissing balloon inflation (KBI) under OCT/optical frequency domain imaging (OFDI) guidance. Inter- and intra-observer agreement regarding the assessment of 3D bifurcation types were 0.88 and 0.94, respectively. The assessment times of 3D-OCT bifurcation type with OCT and OFDI were within about 30 seconds. 3D-OCT bifurcation types showed the greatest correlation with the distal bifurcation angle assessed by 3D-QCA among the three bifurcation angles (distal bifurcation angle, proximal bifurcation angle and main vessel angle), and the optimal cut-off distal bifurcation angle to predict a perpendicular type bifurcation, as determined by ROC analysis, was 51.0° (AUC 0.773, sensitivity 0.80, specificity 0.67). Based on this cut-off value for the distal bifurcation angle (51°), the diagnostic accuracy for perpendicular type bifurcation in cases with a BA ≥ 51° (n = 34) was 70.6% (24/34) and that of the parallel type bifurcation in cases of BA < 51° (n = 26) was 76.9% (20/26).
Performing 3D-OCT for assessment of coronary artery bifurcation type is feasible and simple, and can be done in a short time with high reproducibility.
Performing 3D-OCT for assessment of coronary artery bifurcation type is feasible and simple, and can be done in a short time with high reproducibility.Rapid screening and diagnosis of coronavirus disease 2019 in the emergency department is important for controlling infections. When polymerase chain reaction tests cannot be rapidly performed, rapid antigen testing is often used, albeit with insufficient sensitivity. Therefore, we evaluated the diagnostic accuracy of combining rapid antigen and antibody test results. This was a retrospective review of patients who visited our emergency department between February and May 2021 and underwent rapid antigen, immunoglobulin G antibody, and reverse transcription-polymerase chain reaction tests. The study included 1,070 patients, of whom 56 (5.2%) tested positive on reverse transcription-polymerase chain reaction. The sensitivity, specificity, and area under the curve of rapid antigen testing were 73.7%, 100.0%, and 0.87, respectively. The combined rapid antigen and antibody test result had improved diagnostic accuracy, with 91.2% sensitivity, 97.9% specificity, and an area under the curve of 0.95. The results of the rapid antigen and antibody tests could be combined as a reliable alternative to reverse transcription-polymerase chain reaction.Many biosynthetic pathways produce pyrophosphate (PPi) as a by-product, which is cytotoxic if accumulated at high levels. Pyrophosphatases play pivotal roles in PPi detoxification by converting PPi to inorganic phosphate. A number of apicomplexan parasites, including Toxoplasma gondii and Cryptosporidium parvum, express a PPi-dependent phosphofructokinase (PPi-PFK) that consumes PPi to power the phosphorylation of fructose-6-phosphate. However, the physiological roles of PPi-PFKs in these organisms are not known. Here, we report that Toxoplasma expresses both ATP- and PPi-dependent phosphofructokinases in the cytoplasm. Nonetheless, only PPi-PFK was indispensable for parasite growth, whereas the deletion of ATP-PFK did not affect parasite proliferation or virulence. The conditional depletion of PPi-PFK completely arrested parasite growth, but it did not affect the ATP level and only modestly reduced the flux of central carbon metabolism. However, PPi-PFK depletion caused a significant increase in cellular PPi and decreased the rates of nascent protein synthesis. The expression of a cytosolic pyrophosphatase in the PPi-PFK depletion mutant reduced its PPi level and increased the protein synthesis rate, therefore partially rescuing its growth. These results suggest that PPi-PFK has a major role in maintaining pyrophosphate homeostasis in T. gondii. This role may allow PPi-PFK to fine-tune the balance of catabolism and anabolism and maximize the utilization efficiency for carbon nutrients derived from host cells, increasing the success of parasitism. Moreover, PPi-PFK is essential for parasite propagation and virulence in vivo but it is not present in human hosts, making it a potential drug target to combat toxoplasmosis.
Preterm birth is the leading cause of neonatal morbidity and mortality. The recurrence rate of spontaneous preterm birth is high, and additional preventive measures are required. Our objective was to assess the effectiveness of low-dose aspirin compared to placebo in the prevention of preterm birth in women with a previous spontaneous preterm birth.
We performed a parallel multicentre, randomised, double-blinded, placebo-controlled trial (the APRIL study). The study was performed in 8 tertiary and 26 secondary care hospitals in the Netherlands. We included women with a singleton pregnancy and a history of spontaneous preterm birth of a singleton between 22 and 37 weeks. Participants were randomly assigned to aspirin 80 mg daily or placebo initiated between 8 and 16 weeks of gestation and continued until 36 weeks or delivery. Randomisation was computer generated, with allocation concealment by using sequentially numbered medication containers. Participants, their healthcare providers, and researchers were ps//www.trialregister.nl/trial/5553.
Central aortic arterial stiffness (CAAS) is an independent cardiovascular risk factor. Insulin resistance (IR) contributes to CAAS-associated risk.
To evaluate the association between IR and CAAS in a Mexican population without diabetes.
IR was estimated with Homeostatic Model Assessment 2-Insulin Resistance (HOMA2-IR) and other surrogate markers (Metabolic score for IR [METS-IR], Quantitative Insulin Sensitivity Check Index [QUICKI], triglycerides/glucose index [TyG], TyG*body mass index [TyG*BMI] and triglycerides/high-density lipoprotein cholesterol ratio [TG/HDL-C]). CAAS was evaluated using carotid-femoral pulse wave velocity analysis (PWV
) and the standardized augmentation index (AI-75). Bivariate correlations were made between surrogate markers and PWV
. Increased CAAS was defined as PWV
above the 90
percentile. Thresholds and area under the curve (AUC) were obtained for each surrogate marker in order to evaluate their performance in estimating increased CAAS.
Three hundred and fifty-eight patients were included. A correlation was found between HOMA2-IR and PWV
; this correlation was replicated with other surrogate markers. METS-IR and TyG*BMI had the highest degree of correlation with PWV
. When adjustments were made for covariates, the correlations with TyG*BMI, METS-IR, HOMA2-IR and QUICKI maintained significance. HOMA2-IR showed the strongest correlation with AI-75. METS-IR and TyG showed the best AUC. Patients with prediabetes had the highest PWV
.
The relationship between IR and CAAS is present before the onset of diabetes; this association may entail higher cardiovascular risk.
The relationship between IR and CAAS is present before the onset of diabetes; this association may entail higher cardiovascular risk.
To evaluate the effect of azithromycin (AZM) on biofilm formation and composition in multidrug resistant (MDR) Acinetobacter baumannii.
Ninety-six A. baumannii isolates were studied. Antimicrobial susceptibility and sub-minimum inhibitory concentration (sub-MIC) were determined by the broth microdilution method. Carbapenemase genes were detected by polymerase chain reaction and clonal diversity by pulsed-field gel electrophoresis (PFGE). Biofilm formation without AZM and AZM sub-MIC were determined by crystal violet staining. AZM-free biofilm composition and AZM sub-MIC were determined by detachment assays.
The selected A. baumannii were MDR; 93.8% were carbapenem-resistant and 24 were OXA-24-positive. PFGE showed predominance of clones A (53%), B (34.7%) and C (12.5%). Biofilm production at AZM sub-MICs decreased in 53.1%, increased in 34.7% and showed no differences in 12.5% of isolates, in comparison with biofilm production without AZM.
AZM sub-MIC can reduce biofilm production in A. baumannii MDR isolates with decreased protein and DNA in the biofilm. Our results may be useful in synergy studies for new therapeutic alternatives.
AZM sub-MIC can reduce biofilm production in A. baumannii MDR isolates with decreased protein and DNA in the biofilm. Our results may be useful in synergy studies for new therapeutic alternatives.