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Research quality in pediatric surgery has been challenged by multiple factors, including the low incidence of some congenital pathologies and rare event rates. With the rapid increase of pediatric surgical literature, there is a need for systematic reviews to synthesize evidence. It is important to assess the quality of these systematic reviews.This study aims to examine the reporting of systematic reviews and meta-analyses, using inguinal hernia repair as an index diagnosis.MEDLINE, Embase, and CINAHL databases were searched for systematic reviews and/or meta-analyses of interventions on inguinal hernia in the pediatric population. The quality reporting was assessed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and A MeaSurement Tool to Assess Systematic Reviews (AMSTAR) 2 tools.Of 1449 unique reports, 21 studies were included (15 meta-analyses and six systematic reviews). Median percent reported items for PRISMA and AMSTAR 2 were 72.2% and 70.5%, respectively. The least reported items in PRISMA were protocol registration (27.6%), synthesis of results (13.0%), and a risk of bias across studies (20.6%). For AMSTAR 2, the least reported items were reporting of source of funding (14.3%), appropriate methods for statistical combination of results (25.0%), and pre-establishment of protocol (28.6%). All critical items were completely or partially fulfilled in 5/21 (23.8%) of the studies and completely absent in 1/21 (4.8%) studies.The results of this study highlight relatively good reporting quality, yet a poor methodological quality of systematic reviews/meta-analyses in the pediatric surgery literature on inguinal hernia management.

Background While coronary computed tomography angiography (CCTA) provides comprehensive anatomic evaluation of coronary artery disease (CAD) with prognostic implications, clinically, the focus is usually placed on presence or absence of functionally significant CAD. Herein, we aimed to suggest a new risk stratification strategy using CCTA in patients with anatomic CAD but without myocardial ischemia on single-photon emission computed tomography (SPECT). Methods Consecutive patients (n = 798) with CAD on CCTA who underwent SPECT for evaluation of myocardial ischemia were retrospectively evaluated. The primary outcome was the occurrence of adverse cardiac events, including cardiac death, nonfatal myocardial infarction, unstable angina, and late revascularization. Results Of the enrolled patients, 542 (68%) showed no perfusion defect (PD) on SPECT. During the follow-up (median, 22.6 months), adverse cardiac events occurred in 23 patients without PD (4.6%). Presence of plaque in ≥4 coronary segments, plaque in the left main or proximal left anterior descending coronary artery, and partially calcified plaque presence were independent predictors of adverse events. When we defined the CCTA score based on these 3 predictors (0–3 points), the annualized event rates increased with increasing CCTA scores. Patients with a CCTA score of 3 were associated with a 23-fold risk increase (adjusted HR 23.18; p = 0.003) and showed unfavorable event-free survival, comparable to those with PD on SPECT (p = 0.191). Conclusion Anatomic CAD patients without evidence of myocardial ischemia on SPECT but with high-risk characteristics on CCTA showed unfavorable outcomes, comparable to those with PD. CCTA allows further risk stratification even in patients with negative SPECT findings.

The rise of domestic fringe groups within the United States has been well documented, threatening political and social stability. The QAnon conspiracy theory has developed as one such destructive group, though it remains a largely misunderstood movement. Through a mixed-methods analysis of over 3.5 million messages on Telegram from three politically extreme communities - QAnon, far-right, and far-left - we studied how QAnon fits within the larger non-mainstream political ecosystem. Our analysis provides insights into how this new political movement is dissimilar to the far-right or the far-left but shares offline interests with the far-right. The topics discussed within QAnon communities were unique to the movement and the least reactive to news cycles. Links shared by QAnon, particularly from YouTube and Twitter, were often from traditional conservative sources and individuals, whereas the far-left and far-right relied on less mainstream sources. Finally, though QAnon may be distinct from the other communities, it coalesces with the far-right during particular political events where the former United States President Trump is a major player. Our findings highlight how fringe groups react to major political events and navigate conversations online.

Two actinomycetes, a member of the rare halophilic genus Streptomonospora and a Nocardiopsis sp. (Nocardiopsaceae), strains CNQ-082 and CNQ-675, respectively, were isolated from marine sediments collected off shore near La Jolla, California. HPLC-UV guided fractionations of the extracts of these strains yielded marinopyrones A–D ( 1 – 4 ), the structures of which were elucidated by interpretation of 1D and 2D NMR and HRMS spectroscopic data. Oxidative ozonation, followed by conversion of the acid product to an α-naphthyl amide, provided the absolute configuration at the chiral center on the side-chain. Marinopyrones A–D were examined for the inhibitory activity on nitric oxide production in LPS-activated mouse macrophage cells (RAW 264.7); marinopyrone D ( 4 ) was inhibitory with an IC 50 value of 13 μM. To our knowledge, marinopyrones A–C are only the second reported natural products from the rare halophilic genus Streptomonospora .

In this study, a simulation of layout rearrangement in grinding/classification process was conducted to increase the throughput of an industrial plant processing 5.9 t/h of gold ore in Jeollanamdo province, Korea. The layout was rearranged to maintain the final product particle size while restoring the loss of throughput that has resulted from recent developments in mines. The process is composed of two-stage circuit, the first stage is an open circuit of the first ball mill and spiral classifier, and the second stage is a closed circuit of the second ball mill and hydrocyclone. Particle size distributions of each streams were predicted through simulation, using the population balance (PBM), Stokes’ and Plitt’s models for the ball mill, spiral classifier, and hydrocyclone, respectively. Lab-scale parameters for PBM were obtained by conducting batch grinding tests. The obtained lab-scale parameters were scaled-up using an empirical scale-up equation based on the industrial plant conditions. Using the obtained particle size distributions, the reduction ratio based on the 80% passing size was calculated to be 80.5 for the first ball mill, while it was only 1.19 for the second ball mill. To solve the process imbalance problem, a layout rearrangement that involves the switching of the first and second ball mills in the process was proposed. The final product was finer, with the 50% passing size reducing from 35 μ m to 31 μ m . The throughput of the industrial plant can therefore be increased by approximately 36% to 8 t/h. This study provides the guideline of the methodology which can help in adapting the simulation of layout rearrangement in the grinding/classification process for an industrial plant.

Both microscopic and macroscopic impacts of the electromagnetic effects on blob dynamics are considered. Linear stability analysis and nonlinear BOUT++ simulations demonstrate that electromagnetic effects in high temperature or high beta plasmas suppress the resistive drift wave turbulence in the blob when resistivity drops below a certain value. In the course of blob’s motion in the SOL its temperature is reduced, which leads to enhancement of resistive effects, so the blob can switch from electromagnetic to electrostatic regime, where resistive drift wave turbulence become important. It is found that inhomogeneity of magnetic curvature or plasma pressure along the filament length leads to bending of the high-beta blob filaments. This is caused by the increase of the propagation time of plasma current (Alfven time) in higher-density plasma. The effects of sheath boundary conditions on the part of the blob away from the boundary are also diminished by the increased Alfven time.

We investigated the pharmacokinetic profile of (R)- and (S)-zaltoprofen (ZPF) in rats using rapid and selective liquid chromatography with solid-phase extraction (SPE). The ZPF enantiomers were extracted from a small volume of plasma (0.2 mL) by means of SPE using cartridges and were analyzed on a Chiralcel OJ-H (4.6 mm × 150 mm, 5 μm) column with ultraviolet detection at 244 nm. The lower limit of quantification of the ZPF enantiomers in plasma was 0.1 μg/mL. The validated method was successfully applied to chiral pharmacokinetic studies of oral administration of racemic ZPF to rats. (S)-ZPF showed significantly higher AUC, T max , and C max and a longer half-life than (R)-ZPF, indicating higher bioavailability of the (S)-isomer. A total of 8 samples (about 12% of the total number of samples) were selected for incurred sample reanalysis (ISR). The % difference between the re-assay concentrations and the original concentrations were all less than 15% of their mean values and met the acceptance criteria for ISR.

This study established ultra-performance liquid chromatography coupled with a photodiode array detector for determining psilocin and its pharmacokinetics in rat plasma after orally administering an extract of Gymnopilus spectabilis. The extract was separated on an ODS C18 column (2.3 μm, 100 mm × 2.1 mm I.D.) by gradient elution with (A) water containing 50mM AcONH(4) and (B) acetonitrile. The wavelength was set at 265 nm and the injection volume was 10 μL. Under these conditions, the calibration curve was linear over the concentration range 0.2-20 μg/mL with a correlation coefficient of r(2)=0.9992. The inter- and intraday precision levels were less than 7% and the accuracies (%) were within the range 92.0-102.5%. The method was sufficiently valid to be applied to a pharmacokinetics study of psilocin in rat plasma. The pharmacokinetic parameters of psilocin in rat plasma after the oral administration of a G. spectabilis extract were as follows: C(max), 0.43 ± 0.12 μg/mL; T(max), 90 ± 2.1 min; AUC(0→t), 1238.3 ± 96.4 (μg/mL) min; and T(1/2), 117.3 ± 40.3 min.

Chiral stationary phases were synthesized and their ability to separate racemic precursors from which they were derived was assessed. Taken in conjunction with homochiral recognition previously observed in the solid state, the results of this study reveal that a geometrically controlling π–π interaction has a profound influence on molecular recognition.

The current study demonstrates the reversal of enantiomer migration order (EMO) in capillary electrophoresis (CE) based separations of sibutramines (SIB) as a function of the concentration of two types of cyclodextrin (CD), native β-CD and acetyl-β-CD. At normal working concentrations (10mM) of either CD, (S)-SIB migrated first. However, at CD concentrations greater than 10mM, (R)-SIB was the first to migrate. This study describes factors involved in determining EMO for sibutramine enantiomers at low and high concentrations of CDs. The reversal of EMO could be explained in terms of the opposing effects of the stability and the limiting complex mobility of the SIB-CD complexes. The enantioseparation of SIB with methyl- and 2-hydroxypropyl-β-CD was possible based on differences in the binding constants of complexes. However, reverse EMO was not observed because of equal mobilities of SIB enantiomers complexed with methyl- and 2-hydroxypropyl-β-CD.

The present study aimed to design the liposomal delivery system for TD53, a novel algicial drug in order to improve the delivery properties of TD53 and evaluate its algicidal effects as well as selectivity against harmful and non-harmful algae. Liposomes of TD53 were prepared with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) by a lyophilization, resulting in relatively small size vesicles (234±38nm) and narrow size distribution (PI=0.130±0.027). The drug leakage from the liposome was negligible in the F/2 media (

(-)-(18-Crown-6)-2,3,11,12-tetracarboxylic acid-bonded silica was used as the chiral stationary phase in capillary electrochromatography (CEC) for enantioseparation of some alpha-amino acids. Separation data in CEC were measured in mobile phases of varying pH, and composition of methanol and buffer, and compared with those in capillary liquid chromatography (CLC). In CEC better enantioseparation was generally obtained in the eluent of lower pH, higher buffer concentration and intermediate MeOH content, usually at the expense of analysis time. CEC showed generally better enantioselectivity and resolutions than CLC for the amino acids investigated.

A biologically active benzophenanthridine alkaloid, 6-methoxydihydrosanguinarine (MS), was isolated from Hylomecon plants. Although enantiomers of MS can be separated by chiral HPLC, its isomers rapidly form a racemic mixture in methanol. The rate constants for the racemization of MS enantiomers were 9.20 × 10 −4 s −1 and 9.95 × 10 −4 s −1 for (+)-MS and (−)-MS, respectively, as determined by dynamic HPLC and chiral chromatography. This unusually rapid racemization may originate from the formation of a stable iminium ion intermediate, sanguinarine. Therefore, the variety of biological activities exhibited by MS may be attributable to a combination of (+)-MS, (−)-MS, and sanguinarine.

Biodegradable polymer microspheres have been successfully utilized as a medium for controlled protein or peptide-based drug release. Because the release kinetics has been typically controlled by modulating physical or chemical properties of the medium, these parameters must be optimized to obtain a specific release profile. However, due to the complexity of the release mechanism and the complicated interplay between various design parameters of the release medium, detailed prediction of the resulting release profile is a challenge. Herein we suggest a simple method to target specific release profiles more efficiently by integrating release profiles for an array of different microsphere types. This scheme is based on our observation that the resulting release profile from a mixture of different samples can be predicted as the linear summation of the individually measured release profiles of each sample. Hence, by employing a linear equation at each time point and formulating them as a matrix equation, we could determine how much of each microsphere type to include in a mixture in order to have a specific release profile. In accordance with this method, several targeted release profiles were successfully obtained. We expect that the proposed method will allow us to overcome limitations in controlling complicated release mechanisms so that drug delivery systems can be reliably designed to satisfy clinical demands.

The liquid chromatographic enantiomerPDF separation of nonsteroidal anti-inflammatory drugs (NSAIDs) was performed on covalently immobilized chiral stationary phases (CSPs) (Chiralpak IA, Chiralpak IB, and Chiralpak IC) and coated-type CSPs (Chiralpak AD and Chiralcel OD) derived from polysaccharide derivatives. The chromatographic conditions were as follows: the flow rate was 1.0 ml min−1, the detection wavelength was 254 nm, and the standard mobile phase was 2-propanol/hexane/trifluoroacetic acid on all CSPs. A mobile phase of 2-propanol/hexane/trifluoroacetic acid = 10:90:0.1 (v/v) and 2:98:0.1 (v/v) were used on Chiralpak AD and Chiralcel OD of coated-type CSPs, respectively. Several solvents (dichloromethane, tetrahydrofuran, and ethyl acetate) in the mobile phase were used on covalently immobilized CSPs (Chiralpak IA, Chiralpak IB, and Chiralpak IC) and, therefore, solvent versatility of the covalently immobilized CSPs for enantiomer separation of NSAIDs was shown. Also, chromatographic comparisons for enantiomer resolution of these analytes were made on amylose tris (3,5-dimethylphenylcarbamate) derived CSPs (Chiralpak IA and Chiralpak AD) and cellulose tris (3,5-dimethylphenylcarbamate) derived CSPs (Chiralpak IB and Chiralcel OD), respectively. The results indicated that Chiralpak IA and Chiralpak IB showed generally lower enantiomer separation than Chiralpak AD and Chiralcel OD, respectively.

Liquid chromatographic comparisons for enantiomer resolution of α-amino acids and chiral primary amino compounds were made using chiral stationary phases (CSPs) prepared by covalently bonding (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) of the same chiral selector. The resolution of all α-amino acids on CSP 1 developed in our group was found to be better than that on CSP 2 reported by Machida et al. All α-amino acids examined in this study were well enantioseparated on CSP 1 (α=1.22–2.47), while four analytes were not resolved or all the other analytes were poorly resolved on CSP 2 than on CSP 1. However, in resolving the primary amino compounds without a carbonyl group, CSP 1 was comparable with CSP 2. Although (+)-18-C-6-TA of the same chiral selector was used to prepare CSP 1 and CSP 2, this study showed that different connecting methods for the CSPs might influence their ability to resolve the analytes depending on their structures related to the chiral recognition mechanism.