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This article argues that it is time for a more comprehensive review of Australian law relating to human germline cell genetic engineering. We do not aim to take an ethical stance. Rather, we argue that broader reform and review are necessary in order to come to a suitable ethical stance, and for legislation to reflect that ethical stance adequately rather than inhabiting the corridors of vagary. The need for this has arisen gradually over the past decade, as around the world more countries are developing their capabilities in this field. As such, regulation is of increasing importance either to facilitate further research, or adequately block inappropriate research. Australia's current regulation in comparison contains uncertainty and lacks conviction. We argue that in order to ensure this area is governed primarily by what is in the public interest a review is in order., Competing Interests: None.

Background and Aims: Endoscopic dilation (ED) is still the mainstay of therapeutic management of benign esophageal strictures (BESs). This study aimed to establish risk factors for refractory BESs and assess long-term clinical outcomes of ED., Methods: We performed a retrospective study in 891 patients who underwent ED from 2003 to 2018 for BESs. We searched electronic medical records in 6 tertiary care centers in the Netherlands for data on clinical outcome of ED. Median follow-up was 39 months. The primary endpoint was risk factors for refractory BESs, defined as factors associated with an increased number of ED sessions during follow-up. Secondary endpoints were time from first to last ED session and adverse events., Results: Dilation up to 13 to 15 mm was associated with a higher number of ED sessions than dilation up to 16 to 18 mm (5.0 vs 4.1; hazard ratio [HR], 1.4; P = .001). Compared with peptic strictures, anastomotic (4.9 vs 3.6; HR, 2.1; P < .001), radiation (5.0 vs 3.6; HR, 3.0; P < .001), caustic (7.2 vs 3.6; HR, 2.7; P < .001), and postendotherapy (3.9 vs 3.6; HR, 1.8; P = .005) strictures were associated with a higher number of ED sessions. After 1 year of follow-up, the proportions of patients who remained free of ED was 75% in anastomotic, 71% in radiation, 70% in peptic, 83% in postendotherapy, and 62% in caustic strictures. Esophageal perforation occurred in 23 ED sessions (.4%) in 22 patients (2.4%)., Conclusions: More than 60% of patients with BESs remain free of ED after 1 year of follow-up. Because dilation up to 16 to 18 mm diameter was associated with fewer ED sessions during follow-up, we suggest that clinicians should consider dilation up to at least 16 mm to reduce the number of ED sessions in these patients., (Copyright © 2020 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Background and Objectives: Patients with severe influenza virus infection, multi-organ failure and organ replacement therapy may absorb and metabolize neuraminidase inhibitors differently. Systematic pharmacokinetic/pharmacodynamic clinical trials are currently lacking in this high-risk group. Inadequate dosing increases the risk of treatment failure and drug resistance, especially in severely ill patients with elevated virus loads. This study aims to explore the impact of organ replacement therapy on oseltamivir drug concentrations., Methods: Serial pharmacokinetic/pharmacodynamic measurements and Sieving coefficients were assessed in two patients with severe influenza B infection requiring organ replacement therapy., Results: Patient #1, a 9-year-old female with severe influenza B virus infection, biventricular assist device, and continuous veno-venous hemodiafiltration, received 75 mg oral oseltamivir twice-daily for 2 days, then intravenous oseltamivir with one-time renoprotective dosing (40 mg), followed by regular intravenous administration of 100 mg twice-daily. Plasma oseltamivir carboxylate concentrations were stable initially, but only regular administration of 100 mg resulted in virus load decline and clinical improvement. Patient #2, a 28-year-old female with influenza B virus infection requiring extracorporeal membrane oxygenation, received 75 mg oral oseltamivir twice-daily, resulting in erratic oseltamivir blood concentrations. In both patients, drug concentrations remained well within safety margins., Conclusions: In severe cases with multi-organ failure, administration of 100 mg intravenous oseltamivir twice-daily provided reliable drug concentrations, as opposed to renoprotective and oral dosing, thereby minimizing the risk of treatment failure and drug resistance. Evidence-based pediatric dosing recommendations and effective intravenous antiviral treatment modalities are needed for intensive care patients with life-threatening influenza disease.

Interference testing of co-medication in bioanalytical method validation has become an area of debate in view of the increased specificity offered by current state-of-the-art technology in both LC-MS/MS and ligand-binding assay platforms. In view of this, and considering the extensive experience within the European Bioanalysis Forum member companies, we evaluated the impact of co-medication on the performance of hundreds of bioanalytical methods with the aim of providing a science-based recommendation on how to evaluate and document potential interference from co-medication on the PK parameters in clinical studies in patients and volunteers.

Since 2008, blood stability testing has gained considerable attention in the European Bioanalysis Forum (EBF) with discussions aiming to align processes, timing and reporting of analyte stability testing in blood as part of method development and validation. In this recommendation, EBF summarizes the conclusions reached to date and aims to provide recommendation for the experimental conduct of such assays as well as the inclusion of stability testing into the scope of method development and validation. Besides considering a step-wise approach for blood stability testing, recommendation is made to analyze the blood fraction using a qualified assay in order to circumvent important experimental hurdles. This article will provide an increased understanding of the impact of blood stability testing but furthermore invites scientists to share their views in order to refine the thinking to reach a global harmonized view.

Sugammadex is a modified γ-cyclodextrin which rapidly reverses rocuronium-and vecuronium-induced neuromuscular blockade. Previous studies suggest that sugammadex is mostly excreted unchanged via the kidneys. This single-center, open-label, non-randomized study used (14)C-labeled sugammadex to further investigate the excretion, metabolic and pharmacokinetic (PK) profiles of sugammadex in six healthy male volunteers. (14)C-labeled sugammadex 4 mg/kg (0.025 MBq/kg of (14)C-radioactivity) was administered as a single intravenous bolus. Blood, urine, feces and exhaled air samples were collected at pre-defined intervals for assessment of sugammadex by liquid chromatography-mass spectrometry (LC-MS) and for radioactivity measurements. Adverse events were also assessed. Excretion of sugammadex was rapid with ∼70% of the dose excreted within 6 h and ∼90% within 24 h. Less than 0.02% of radioactivity was excreted in feces or exhaled air. Ninety-five percent of the radioactivity detected in urine could be attributed to sugammadex, as determined by LC-MS, suggesting very limited metabolism of sugammadex. LC-MS analysis of plasma samples found that sugammadex accounted for 100% of total (14)C-radioactivity in the plasma. In general, PK parameters determined from radioactivity and sugammadex plasma concentrations were very similar. Any adverse events were of mild-to-moderate intensity, and judged unrelated to sugammadex. These findings demonstrate that sugammadex is cleared rapidly, almost exclusively via the kidney, with minimal or no metabolism., (Copyright © 2011 John Wiley & Sons, Ltd.)

Following intensive discussions, review, alignment of procedures and multiple surveys among their member companies, the European Bioanalysis Forum (EBF) is providing a recommendation on how to integrate incurred sample reproducibility (ISR) in the bioanalytical process. The recommendation aims to provide guidance throughout the lifecycle of a validated method, including the application of the method in study support. In its recommendation, the EBF considers both the internal discussions with EBF member companies, as well as the input provided in international meetings where ISR was discussed. The ultimate goal of the EBF recommendation is to ensure that bioanalytical methods can provide accurate and reproducible concentration data for pharmacokinetic and/or toxicokinetic evaluation, without any compromise, while safeguarding the optimal use of laboratory resources.

Novel as well as known 5'-N-substituted carboxamidoadenosines were prepared via new routes that provided shorter reaction times and good yields. Binding affinities were determined for rat A1 and A2A receptors and human A3 receptors. EC50 values were determined for cyclic AMP production in CHO cells expressing human A2B receptors. On all receptor subtypes relatively small substituents on the carboxamido moiety were optimal. Selectivity for the A3 receptor was found for several analogues (1a, 1d, 1h, and 1k). On A1 receptors a number of compounds, but not 5'-N-ethylcarboxamidoadenosine (NECA, 1b), showed small GTP shifts, which could be indicative of lower intrinsic activities at the A1 receptor. At the A2B receptor, derivatives 1i-k with modified ethyl substituents had reduced activities compared to the A2B reference agonist NECA (1b). Thiocarboxamido derivatives (8b and 8c) displayed considerable although decreased A2B receptor activity. The X-ray structure determination of compound 8b was carried out. Due to intramolecular hydrogen bonding between the carboxamido NH and the purine N3 in the crystal structure, the ribose moiety of this compound is in a syn conformation. However, theoretical calculations support that NECA (1b), and less so 8b, can readily adopt both the syn and the anti conformation, therefore not excluding the proposed anti mode of binding to the receptor.

The adenosine antagonist 9-chloro-2-(2-furanyl)[1,2,4]triazolo[1, 5-c]quinazolin-5-amine (CGS 15943) binds nonselectively to human A1, A2A, and A3 receptors with high affinity. Acylated derivatives and one alkyl derivative of the 5-amino group and other modifications were prepared in an effort to enhance A2B or A3 subtype potency. In general, distal modifications of the N5-substituent were highly modulatory to potency and selectivity at adenosine receptors, as determined in radioligand binding assays at rat brain A1 and A2A receptors and at recombinant human A3 receptors. In Chinese hamster ovary cells stably transfected with human A2B receptor cDNA, inhibition of agonist-induced cyclic AMP production was measured. An N5-(2-iodophenyl)acetyl derivative was highly selective for A2A receptors. An (R)-N5-alpha-methyl(phenylacetyl) derivative was the most potent derivative at A3 receptors, with a Ki value of 0.36 nM. A bulky N5-diphenylacetyl derivative, 13, displayed a Ki value of 0. 59 nM at human A3 receptors and was moderately selective for that subtype. Thus, a large, nondiscriminating hydrophobic region occurs in the A3 receptor in proximity to the N5-substituent. A series of straight-chain N5-aminoalkylacyl derivatives demonstrated that for A2B receptors the optimal chain length occurs with three methylene groups, i.e., the N5-gamma-aminobutyryl derivative 27 which had a pA2 value of 8.0 but was not selective for A2B receptors. At A1, A2A, and A3 receptors however the optimum occurs with four methylene groups. An N5-pivaloyl derivative, which was less potent than 27 at A1, A2A, and A3 receptors, retained moderate potency at A2B receptors. A molecular model of the 27-A2B receptor complex based on the structure of rhodopsin utilizing a "cross-docking" procedure was developed in order to visualize the environment of the ligand binding site.

Various adenosine analogues were tested at the adenosine A2B receptor. Agonist potencies were determined by measuring the cyclic AMP production in Chinese Hamster Ovary cells expressing human A2B receptors. 5'-N-Substituted carboxamidoadenosines were most potent. 5'-N-Ethylcarboxamidoadenosine (NECA) was most active with an EC50 value of 3.1 microM. Other ribose modified derivatives displayed low to negligible activity. Potency was reduced by substitution on the exocyclic amino function (N6) of the purine ring system. The most active N6-substituted derivative N6-methyl-NECA was 5 fold less potent than NECA. C8- and most C2-substituted analogues were virtually inactive. 1-Deaza-analogues had a reduced potency, 3- and 7-deazaanalogues were not active.

A series of both aliphatic and aromatic amides and aromatic amidines derived from 2-amino-1,10-phenanthroline (3) according to the Topliss scheme were synthesized and subsequently tested for antimycoplasmal potency. Although the compounds themselves showed no activity, in the presence of a nontoxic copper concentration of 40 microM all compounds appeared to be very active against Mycoplasma gallisepticum K154. The most active compounds were found in the amide series and show growth inhibition in the nanomolar range. These compounds are 4 times more active than tylosin, a macrolide antibiotic, which is used therapeutically in veterinary practice. In the presence of copper, amides derived from 3 are more active than corresponding amidines. Increased activity following derivatization of 3 may be due to the presence of a third coordination site for copper in the title compounds. Evaluation of biological data revealed that antimycoplasmal activity of amides derived from 3 is dependent on lipophilicity. For these amides a good linear correlation was found between antimycoplasmal activity and hydrophobic fragmental values for substituents considered. This quantitative structure-activity relationship study indicated that antimycoplasmal activity was increased upon a decrease of these hydrophobic fragmental values.

The influence of the steric hindrance of halogen substituents was investigated in vitro by measuring the activity of yeast aldehyde dehydrogenase (aldehyde: NAD(P)+ oxidoreductase, EC 1.2.1.5) and of aldehyde dehydrogenases in subcellular rat liver fractions with a series of ortho- and para-halo-substituted benzaldehydes as substrates. Upon an increase in the size of the halogen substituent (F, Cl, Br), the reactivity of yeast aldehyde dehydrogenase to ortho-substituted benzaldehydes decreased drastically. The same phenomenon was observed with the unspecific aldehyde dehydrogenases in three rat liver fractions; cytoplasm, mitochondria and microsomes. The corresponding para-halobenzaldehydes (F, Cl, Br, I) did not reveal large differences in reactivity to the various rat liver aldehyde dehydrogenases. The aldehyde dehydrogenases in the rat liver microsomal fraction exhibited most clearly the regiospecificity. Enzymatic oxidation of 4-bromobenzaldehyde was more than 30-times faster then the ortho-isomer. The findings in this investigation confirm the suggestion that the steric hindrance of bulky ortho-substituents of benzaldehydes account for the slowing down of the aldehyde dehydrogenase-catalyzed oxidation of benzaldehydes to corresponding benzoic acids. The enzymatic oxidation of microsomal aldehyde dehydrogenase is strongly influenced by steric effects of benzaldehydes, bearing a halogen in ortho-position. We think that the microsomal aldehyde dehydrogenase might be the principal enzyme responsible for oxidation of halobenzaldehydes in rat liver.

In order to investigate the antimycoplasmal activity of compounds structurally related to 2,2'-bipyridyl, a series of both aliphatic and aromatic amides derived from 1-amino-3-(2-pyridyl)isoquinoline were synthesized. The most active compounds appeared to be as active as Tylosin, an antimycoplasmal therapeutic that is used in veterinary practice, in the presence of a small nontoxic amount of copper. Furthermore, it was found that antimycoplasmal activity depends on the hydrophobic fragmental value of amide residue. A quantitative structure-activity relationship established the optimal hydrophobic fragmental value of the amide residue to be 0.30.

In our search for new compounds with antimycoplasmal activity, a series of aromatic amidines derived from 1-amino-3-(2-pyridyl)isoquinoline (1) was synthesized. In the presence of 40 microM copper the most active compounds show growth inhibition of Mycoplasma gallisepticum in the nanomolar range. These compounds are 3 times as active as tylosin, an antimycoplasmal therapeutic agent that is used in veterinary practice. In the presence of copper, amidines derived from 1 are 2-3 times more active than the corresponding amides. Furthermore it was established that for these compounds too, the presence of a 2,2'-bipyridyl moiety is a necessary prerequisite for antimycoplasmal activity. As for the amides, antimycoplasmal activity of amidines derived from 1 is dependent on the hydrophobic fragmental value of the aromatic nucleus of the amidine moiety. A quantitative structure-activity relationship established the optimal hydrophobic fragmental value of this part of the molecule to be zero.