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This paper proposes a modeling and analysis method for a Caputo–Fabrizio (C-F) definition-based fractional-order Boost converter with fractional-order inductive loads. The proposed method analyzes the system characteristics of a fractional-order circuit with three state variables. Firstly, this paper constructs a large signal model of a fractional-order Boost converter by taking advantage of the state space averaging method, providing accurate analytical solutions for the quiescent operating point and the ripple parameters of the circuit with three state variables. Secondly, this paper constructs a small signal model of the C-F definition-based fractional-order Boost converter by small signal linearization, providing the transfer function of the fractional-order system with three state variables. Finally, this paper conducts circuit-oriented simulation experiments where the steady-state parameters and the transfer function of the circuit are obtained, and then the effect of the order of capacitor, induced inductor, and load inductor on the quiescent operating point and ripple parameters is analyzed. The experimental results show that the simulation results are consistent with those obtained by the proposed mathematical model and that the three fractional orders in the fractional model with three state variables have a significant impact on the DC component and steady-state characteristics of the fractional-order Boost converter. In conclusion, the proposed mathematical model can more comprehensively analyze the system characteristics of the C-F definition-based fractional-order Boost converter with fractional-order inductive loads, benefiting the circuit design of Boost converters. [ABSTRACT FROM AUTHOR]

Abstract: Two amperometric biosensors with immobilized horseradish peroxidase (HRP) were developed for the investigation of the clozapine drug oxidation and for thiols screening based on biosensor signal inhibition. The HRP was retained either in magnetized nanoporous silica microparticles (MMPs) or in a carbon paste (CP). The latter served for the carbon paste electrode while the MMPs were attracted in close proximity of a magnetized carbon electrode. The potential use of these configurations for drug oxidation and inhibition studies was illustrated by the enzymatic oxidation of clozapine (CLZ) in the presence of hydrogen peroxide. The biosensor signal corresponded to the electro-reduction of CLZ oxidation products namely a nitrenium ion (CLZox) generated by the enzyme HRP. Several thiols reactive towards CLZox were investigated and the biosensor signal inhibition (IC50) was comparatively determined. A protective effect of the nanoporous silica and carbon paste matrices towards HRP inactivation was inferred by comparing the biosensor inhibition results with those obtained with the free enzyme in solution. [Copyright &y& Elsevier]

Background: Several clinical trials have demonstrated the efficacy of fluconazole as empiric antifungal therapy in cancer patients with fever and neutropenia. Our objective was to assess the frequency and resource utilization associated with treatment failure in cancer patients given empiric fluconazole antifungal therapy in routine inpatient care. Methods: We performed a retrospective cohort study of cancer patients treated with oral or intravenous fluconazole between 7/97 and 6/01 in a tertiary care hospital. The final study cohort included cancer patients with neutropenia (an absolute neutrophil count below 500 cells/mm3) and fever (a temperature above 38°C or 100.4°F), who were receiving at least 96 hours of parenteral antibacterial therapy prior to initiating fluconazole. Patients' responses to empiric therapy were assessed by reviewing patient charts. Results: Among 103 cancer admissions with fever and neutropenia, treatment failure after initiating empiric fluconazole antifungal therapy occurred in 41% (95% confidence interval (CI) 31% - 50%) of admissions. Patients with a diagnosis of hematological malignancy had increased risk of treatment failure (OR = 4.6, 95% CI 1.5 - 14.8). When treatment failure occurred the mean adjusted increases in length of stay and total costs were 7.4 days (95% CI 3.3 - 11.5) and $18,925 (95% CI 3,289 - 34,563), respectively. Conclusion: Treatment failure occurred in more than one-third of neutropenic cancer patients on fluconazole as empiric antifungal treatment for fever in routine clinical treatment. The increase in costs when treatment failure occurs is substantial. [ABSTRACT FROM AUTHOR]

To systematically explore the effects of polynuclear complexes on the removal of chromium pollutants, a new three-dimensional (3D) microporous metal-organic compound [Cd 3 (HCO 2) 2 (dpa) 4 (bpp) 3 ] n (dpa ​= ​diphenic acid, bpp ​= ​1,3-bi(4-pyridyl)propane) (1) was prepared through hydrothermal synthesis. The structure was characterized by X-ray single crystal diffraction, elemental analysis, and Fourier transform infrared spectroscopy. The results indicate that complex 1 based on Cd(II) clusters is monoclinic and consists of the C 2/ c space group. It exhibits a new 2-nodal (3,5)-connected 3D framework with a Schläfli symbol of {43}{45, 65}. The thermogravimetric analysis (TGA) reveals complex 1 has high thermal stability (stable until 490 ​°C). The photoluminescence shows the emission wavelength of the fluorescence is red-shifted (30 ​nm), and the intensity is significantly increased compared to the free ligand. Adsorption analysis shows that the Cd(II) compound demonstrates significant adsorption towards the dichromate anion (Cr 2 O 7 2−). Its adsorption isotherm is consistent with the Langmuir model and its adsorption kinetics follows a pseudo-second-order model. 3D polynuclear Cd(II) complexes exhibit photo-fluorescent property and adsorption towards the dichromate anion. Image 1 • A new polynuclear coordination polymer [Cd 3 (HCO 2) 2 (dpa) 4 (bpp) 3 ] n has been prepared and characterized. • Cd(II) clusters with 1D+2D→3D framework and a new 2-nodal (3,5)-connected topology. • Robust microporous 1D channel for dichromate removal in an aqueous solution. [ABSTRACT FROM AUTHOR]

Background: Although previous prevalence studies of DED were reported from some countries worldwide, national data are unavailable in China. We aimed to conduct an up-to-date national survey on the prevalence of DED in China and find out the potential risk factors including air pollutant.Methods: 23,922 eligible outpatients were recruited from ophthalmic clinics of 32 cities in China in 2013 by registration orders. The patients' demographic characteristics, history of keratorefractive surgery, diseases and medication history were collected and the daily air pollutant data in 2013. Multivariate logistic analysis was performed to identify the potential risk factors associated with DED. The association between related factors and dry eye diseases subtypes evaluated as p value and odds ratios (OR) with 95% confidence intervals (CI).Results: Among 23,922 outpatients, the prevalence of DED was 61.57%, and that of the male patients was 57.64% and of the female was 65.32% (P < 0.0001). Multivariate logistic regression suggested that the possible risk factors for DED included: female, older age, history of keratorefractive surgery, presence of arthritis, thyroid diseases, and antihistamine, diuretic, duodenal ulcer drugs, diazepam. Air pollutants including O3, PM2.5, and SO2 were also identified as the risk factors.Conclusion: The prevalence of DED among ophthalmic outpatients in China was considerably high. Age, gender, history of keratorefractive surgery, diseases, medication history, and air pollutants were associated with DED prevalence. [ABSTRACT FROM AUTHOR]

Pathological neovascularization is a pivotal biological process in wet age-related macular degeneration (AMD), retinopathy of prematurity (ROP) and proliferative diabetic retinopathy (PDR), in which macrophages (Mφs) play a key role. Tip cell specialization is critical in angiogenesis; however, its interconnection with the surrounding immune environment remains unclear. Succinate is an intermediate in the tricarboxylic acid (TCA) cycle and was significantly elevated in patients with wet AMD by metabolomics. Advanced experiments revealed that SUCNR1 expression in Mφ and M2 polarization was detected in abnormal vessels of choroidal neovascularization (CNV) and oxygen-induced retinopathy (OIR) models. Succinate-induced M2 polarization via SUCNR1, which facilitated vascular endothelial cell (EC) migration, invasion, and tubulation, thus promoting angiogenesis in pathological neovascularization. Furthermore, evidence indicated that succinate triggered the release of RBP4 from Mφs into the surroundings to regulate endothelial sprouting and pathological angiogenesis via VEGFR2, a marker of tip cell formation. In conclusion, our results suggest that succinate represents a novel class of vasculature-inducing factors that modulate Mφ polarization and the RBP4/VEGFR2 pathway to induce pathological angiogenic signaling through tip cell specialization. [ABSTRACT FROM AUTHOR]

To investigate the tolerability and safety of two sublingual tree pollen extracts approved in 2018, a non-interventional study (NIS) was performed. This NIS was an 8-month observational study conducted at 84 sites throughout Germany. Study participants received either a sublingual liquid allergen extract of birch pollen (SBPE) or a liquid allergen extract consisting of a mixture of birch, hazel, and alder tree pollen (STPE). Data from 432 patients were analyzed for the occurrence of adverse events and patient compliance. At least one local reaction occurred in 69 (22.2%) patients, whereas systemic reactions were only observed in 27 (6.3%) patients. STPE-treated patients developed systemic reactions more frequently than SBPE-treated patients (SBPE: 9 (4.3%) vs. STPE: 18 (8.0%)). Only one patient developed a systemic grade III reaction. Severe systemic grade IV reactions were not observed. A total of 348 (98.6%) of the patients who completed all visits were satisfied or very satisfied with the sublingual immunotherapy (SLIT), and 322 (71%) patients completed all visits. Both investigated products were well tolerated by the patients and demonstrated a good safety profile. AEs were observed less frequently than in the preceding clinical phase III trial, and no new safety concerns were identified. [ABSTRACT FROM AUTHOR]

Bacterial endophthalmitis (BE) is an acute eye infection and potentially irreversible blinding ocular disease. The empirical intravitreous injection of antibiotic is the primary treatment once diagnosed as BE. However, the overuse of antibiotic contributes to the drug resistance of pathogens and the retinal toxicity of antibiotic limits its application in clinic. Herein, a cationic aggregation‐induced emission luminogens named with triphenylamine thiophen pyridinium (TTPy) is reported for photodynamic treatment of BE. TTPy can selectively discriminate and kill bacteria efficiently over normal ocular cells. More importantly, TTPy shows excellent antibacterial ability in BE rat models infected by Staphylococcus aureus. Meanwhile, the bacterial killing behavior triggered by TTPy induces innate immune response at an early stage of infection, limiting subsequent robust inflammation and protecting retina from bacterial toxins and inflammation‐induced bystander damage. In addition, TTPy performs better antibacterial ability than commercially used Rose Bengal, suggesting its excellent capability of vision salvage in acute BE. This study exhibits an efficient photodynamic antibacterial treatment to BE, which induces an early intraocular immune response and saves useful vision, endowing TTPy a promising potential for clinical application of ocular infections. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) is a multifactor disease, which is primarily characterized by retinal pigment epithelium (RPE) cell loss. Since the retina is the most metabolically active tissue, RPE cells are exposed to consistent oxidative environment. So, oxidation-induced RPE cell death has long been considered a contributor to the onset of AMD. Here, we applied a retinal degeneration (RD) rat model induced by blue light-emitting diode (LED) and a cell model constructed by H2O2 stimulus to mimic the prooxidant environment of the retina. We detected that the expression of miR-27a was upregulated and the expression of FOXO1 was downregulated in both models. So, we furtherly investigated the role of miR-27a-FOXO1 axis in RPE in protesting against oxidants. Lentivirus-mediated RNA was injected intravitreally into rats to modulate the miR-27a-FOXO1 axis. Retinal function and histopathological changes were evaluated by electroretinography (ERG) analysis and hematoxylin and eosin (H&E) staining, respectively. Massive photoreceptor and RPE cell death were examined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The damage to the retina was aggravated in the FOXO1 gene-knockdown and miR-27a-overexpression groups after exposure to LED but was alleviated in the FOXO1 gene-overexpression or miR-27a-knockdown groups. Dual luciferase assay was used to detect the binding site of miR-27a and FOXO1. Upregulated miR-27a inhibited the expression of FOXO1 by directly binding to the FOXO1 mRNA 3 ′ UTR and decreased the autophagy activity of ARPE-19 cells, resulting in the accumulation of reactive oxygen species (ROS) and decrease of cell viability. The results suggest that miR-27a is a negative regulator of FOXO1. Also, our data emphasize the prominent role of miR-27a/FOXO1 axis in modulating ROS accumulation and cell death in RPE cell model under oxidative stress and influencing the retinal function in the LED-induced RD rat model. [ABSTRACT FROM AUTHOR]

Correlates of acute renal failure in patients receiving parenteral amphotericin B. Background. While parenteral amphotericin B is an effective therapy for serious fungal infections, it frequently causes acute renal failure (ARF). This study identified correlates of ARF in amphotericin B therapy and used them to develop clinical prediction rules. Methods. All 643 inpatients receiving parenteral amphotericin B therapy at one tertiary care hospital were included. Data regarding correlates were obtained both electronically and from manual chart review in a subsample of 231 patients. ARF was defined as a 50% increase in the baseline creatinine with a peak ≥2.0 mg/dL. Results. Among 643 episodes, ARF developed in 175 (27%). In the larger group, the only independent correlate of ARF was male gender (OR = 2.2, 95% CI, 1.5 to 3.3). In the subsample (N = 231), independent correlates of ARF were maximum daily amphotericin dosage, location at the time of initiation of amphotericin therapy, and concomitant use of cyclosporine. These data were used to develop two clinical prediction rules. A rule using only data available at initiation of therapy stratified patients into groups with probability of ARF ranging from 15 to 54%, while a rule including data available during therapy (maximum daily dose) stratified patients into groups with probability of ARF ranging from 4 to 80%. Conclusions. Acute renal failure occurred in a quarter of the patients. Correlates of ARF at the beginning and during the course of amphotericin therapy were identified and then combined to allow stratification according to ARF risk. These data also provide evidence for guidelines for the selection of patients for alternative therapies. [ABSTRACT FROM AUTHOR]

Purpose. The purpose of this meta-analysis was to assess the percent reduction in the intraocular pressure (IOP) after argon laser peripheral iridoplasty (ALPI) and systemic medical therapy in patients with acute primary angle closure (APAC). Methods. We searched a number of electronic databases, including MEDLINE, EMBASE, PubMed, and Cochrane Library. We searched the electronic databases from the inception of the databases to August 2018. The primary outcomes included the IOP reduction (IOPR), percent reduction in IOP (IOPR%) from baseline to the endpoint and peripheral anterior synechiae (PAS). The secondary outcomes included the cup-to-disc ratio (CDR), mean endothelial count, and percent of patients requiring topical glaucoma medication. Summary weighted mean difference (WMD), odds ratio (OR), and 95% confidence intervals (CIs) were calculated. Results. Four eligible studies including 183 eyes (92 in the ALPI group and 91 in the medical therapy group) were identified. When comparing ALPI to medical therapy, the WMDs of the IOPR% were 30.03 (95% CI: 21.33 to 38.72, p<0.00001) at 15 minutes, 27.39 (95% CI: 18.89 to 35.89, p<0.00001) at 30 minutes, 18.15 (95% CI: 10.63 to 25.68, p<0.00001) at 1 hour, and 12.91 (95% CI: 4.50 to 21.32, p=0.003) at 2 hours. There was no statistically significant difference between the two groups at 24 hours and at more than 6 months after therapy. Meanwhile, no significant difference was observed in the degree of PAS, CDR, mean endothelial count, and percent of patients requiring topical glaucoma medication after treatment between the two groups. Conclusions. Both ALPI and systemic medications were effective with regard to decreasing the IOP. ALPI was more effective in lowering the IOP within the first two hours. Therefore, ALPI may be a better choice for rapidly lowering the IOP in patients with APAC within a short period. [ABSTRACT FROM AUTHOR]