Bowel stimulation before loop ileostomy closure to reduce postoperative ileus: a multicenter, single-blinded, randomized controlled trial.

INTRODUCTION: The objective of this study was to evaluate the impact of preoperative bowel stimulation on the development of postoperative ileus (POI) after loop ileostomy closure. METHODS: This was a multicenter, randomized controlled trial (NCT025596350) including adult (≥ 18 years old) patients who underwent elective loop ileostomy closure at 7 participating hospitals. Participants were randomly assigned (1:1) using a centralized computer-generated sequence with block randomization to either preoperative bowel stimulation or no stimulation (control group). Bowel stimulation consisted of 10 outpatient sessions within the 3 weeks prior to ileostomy closure and was performed by trained Enterostomal Therapy nurses. The primary outcome was POI, defined as an intolerance to oral food in the absence of clinical or radiological signs of obstruction, on or after postoperative day 3, that either (a) required nasogastric tube insertion; or (b) was associated with two of the following: nausea/vomiting, abdominal distension, or the absence of flatus. RESULTS: Between January 2017 and November 2020, 101 patients were randomized, and 5 patients never underwent ileostomy closure; thus, 96 patients (47 stimulated vs. 49 control) were analyzed according to a modified intention-to-treat protocol. Baseline characteristics were well balanced in both groups. The incidence of POI was lower among patients randomized to stimulation (6.4% vs. 24.5%, p = 0.034; unadjusted RR: 0.26, 95% CI 0.078-0.87). Stimulated patients also had earlier median time to first flatus (2.0 days (1.0-2.0) vs. 2.0 days (2.0-3.0), p = 0.025), were more likely to pass flatus on postoperative day 1 (46.8% vs. 22.4%, p = 0.022), and had a shorter median postoperative hospital stay (3.0 days (2.0-3.5) vs. 4.0 days (2.0-6.0), p = 0.003). CONCLUSIONS: Preoperative bowel stimulation via the efferent limb of the ileostomy reduced POI after elective loop ileostomy closure.

Selective Oxidations Using a Cytochrome P450 Enzyme Variant Driven with Surrogate Oxygen Donors and Light.

Cytochrome P450 monooxygenase enzymes are versatile catalysts, which have been adapted for multiple applications in chemical synthesis. Mutation of a highly conserved active site threonine to a glutamate can convert these enzymes into peroxygenases that utilise hydrogen peroxide (H2 O2 ). Here, we use the T252E-CYP199A4 variant to study peroxide-driven oxidation activity by using H2 O2 and urea-hydrogen peroxide (UHP). We demonstrate that the T252E variant has a higher stability to H2 O2 in the presence of substrate that can undergo carbon-hydrogen abstraction. This peroxygenase variant could efficiently catalyse O-demethylation and an enantioselective epoxidation reaction (94 % ee). Neither the monooxygenase nor peroxygenase pathways of the P450 demonstrated a significant kinetic isotope effect (KIE) for the oxidation of deuterated substrates. These new peroxygenase variants offer the possibility of simpler cytochrome P450 systems for selective oxidations. To demonstrate this, a light driven H2 O2 generating system was used to support efficient product formation with this peroxygenase enzyme.

Polycation radius of gyration in a polymeric ionic liquid (PIL): the PIL melt is not a theta solvent.

The conformation of the polycation in the prototypical polymeric ionic liquid (PIL) poly(3-methyl-1-aminopropylimidazolylacrylamide) bis(trifluoromethylsulfonyl)imide (poly(3MAPIm)TFSI) was probed using small-angle neutron scattering (SANS) and ultra-small-angle neutron scattering (USANS) at 25 °C and 80 °C. Poly(3MAPIm)TFSI contains microvoids which lead to intense low q scattering that can be mitigated using mixtures of hydrogen- and deuterium-rich materials, allowing determination of the polycation conformation and radius of gyration (Rg). In the pure PIL, the polycation adopts a random coil conformation with Rg = 52 ± 0.5 Å. In contrast to conventional polymer melts, the pure PIL is not a theta solvent for the polycation. The TFSI- anions, which comprise 48% v/v of the PIL, are strongly attracted to the polycation and act like small solvent molecules which leads to chain swelling analogous to an entangled, semi-dilute, or concentrated polymer solution in a good solvent.

Small-Angle Neutron Scattering Insights into 2-Ethylhexyl Laurate: A Remarkable Bioester.

Commercial (protiated) samples of the "green" and biodegradable bioester 2-ethylhexyl laurate (2-EHL) were mixed with D-2-EHL synthesized by hydrothermal deuteration, with the mixtures demonstrating bulk structuring in small-angle neutron scattering measurements. Analysis in a polymer scattering framework yielded a radius of gyration (Rg) of 6.5 Å and a Kuhn length (alternatively described as the persistence length or average segment length) of 11.2 Å. Samples of 2-EHL dispersed in acetonitrile formed self-assembled structures exceeding the molecular dimensions of the 2-EHL, with a mean aggregation number (Nagg) of 3.5 ± 0.2 molecules across the tested concentrations. We therefore present structural evidence that this ester can function as a nonionic (co)surfactant. The available surfactant-like conformations appear to enable performance beyond the low calculated hydrophilic-lipophilic balance value of 2.9. Overall, our data offer an explanation for 2-EHL's interfacial adsorption properties via self-assembly, resulting in strong emolliency and lubricity for this sustainable ester-based bio-oil.

Anion Architecture Controls Structure and Electroresponsivity of Anhalogenous Ionic Liquids in a Sustainable Fluid.

Three nonhalogenated ionic liquids (ILs) dissolved in 2-ethylhexyl laurate (2-EHL), a biodegradable oil, are investigated in terms of their bulk and electro-interfacial nanoscale structures using small-angle neutron scattering (SANS) and neutron reflectivity (NR). The ILs share the same trihexyl(tetradecyl)phosphonium ([P6,6,6,14]+) cation paired with different anions, bis(mandelato)borate ([BMB]-), bis(oxalato)borate ([BOB]-), and bis(salicylato)borate ([BScB]-). SANS shows a high aspect ratio tubular self-assembly structure characterized by an IL core of alternating cations and anions with a 2-EHL-rich shell or corona in the bulk, the geometry of which depends upon the anion structure and concentration. NR also reveals a solvent-rich interfacial corona layer. Their electro-responsive behavior, pertaining to the structuring and composition of the interfacial layers, is also influenced by the anion identity. [P6,6,6,14][BOB] exhibits distinct electroresponsiveness to applied potentials, suggesting an ion exchange behavior from cation-dominated to anion-rich. Conversely, [P6,6,6,14][BMB] and [P6,6,6,14][BScB] demonstrate minimal electroresponses across all studied potentials, related to their different dissociative and diffusive behavior. A mixed system is dominated by the least soluble IL but exhibits an increase in disorder. This work reveals the subtlety of anion architecture in tuning bulk and electro-interfacial properties, offering valuable molecular insights for deploying nonhalogenated ILs as additives in biodegradable lubricants and supercapacitors.

Lipid exchange of apolipoprotein A-I amyloidogenic variants in reconstituted high-density lipoprotein with artificial membranes.

High-density lipoproteins (HDLs) are responsible for removing cholesterol from arterial walls, through a process known as reverse cholesterol transport. The main protein in HDL, apolipoprotein A-I (ApoA-I), is essential to this process, and changes in its sequence significantly alter HDL structure and functions. ApoA-I amyloidogenic variants, associated with a particular hereditary degenerative disease, are particularly effective at facilitating cholesterol removal, thus protecting carriers from cardiovascular disease. Thus, it is conceivable that reconstituted HDL (rHDL) formulations containing ApoA-I proteins with functional/structural features similar to those of amyloidogenic variants hold potential as a promising therapeutic approach. Here we explored the effect of protein cargo and lipid composition on the function of rHDL containing one of the ApoA-I amyloidogenic variants G26R or L174S by Fourier transformed infrared spectroscopy and neutron reflectometry. Moreover, small-angle x-ray scattering uncovered the structural and functional differences between rHDL particles, which could help to comprehend higher cholesterol efflux activity and apparent lower phospholipid (PL) affinity. Our findings indicate distinct trends in lipid exchange (removal vs. deposition) capacities of various rHDL particles, with the rHDL containing the ApoA-I amyloidogenic variants showing a markedly lower ability to remove lipids from artificial membranes compared to the rHDL containing the native protein. This effect strongly depends on the level of PL unsaturation and on the particles' ultrastructure. The study highlights the importance of the protein cargo, along with lipid composition, in shaping rHDL structure, contributing to our understanding of lipid-protein interactions and their behavior.

Structure-Activity Relationships, Deuteration, and Fluorination of Synthetic Cannabinoid Receptor Agonists Related to AKB48, 5F-AKB-48, and AFUBIATA.

Synthetic cannabinoid receptor agonists (SCRAs) are a growing class of new psychoactive substances (NPS) commonly derived from an N-alkylated indole, indazole, or 7-azaindole scaffold. Diversification of this core (at the 3-position) with amide-linked pendant amino acid groups and modular N-alkylation (of the indole/indazole/7-azaindole core) ensures that novel SCRAs continue to enter the illicit drug market rapidly. In response to the large number of SCRAs that have been detected, pharmacological evaluation of this NPS class has become increasingly common. Adamantane-derived SCRAs have consistently appeared throughout the market since 2011, and as such, a systematic set of these derivatives was synthesized and pharmacologically evaluated. Deuterated and fluorinated adamantane derivatives were prepared to evaluate typical hydrogen bioisosteres, as well as evaluation of the newly detected AFUBIATA.

High-Density Lipoprotein function is modulated by the SARS-CoV-2 spike protein in a lipid-type dependent manner.

There is a close relationship between the SARS-CoV-2 virus and lipoproteins, in particular high-density lipoprotein (HDL). The severity of the coronavirus disease 2019 (COVID-19) is inversely correlated with HDL plasma levels. It is known that the SARS-CoV-2 spike (S) protein binds the HDL particle, probably depleting it of lipids and altering HDL function. Based on neutron reflectometry (NR) and the ability of HDL to efflux cholesterol from macrophages, we confirm these observations and further identify the preference of the S protein for specific lipids and the consequent effects on HDL function on lipid exchange ability. Moreover, the effect of the S protein on HDL function differs depending on the individuals lipid serum profile. Contrasting trends were observed for individuals presenting low triglycerides/high cholesterol serum levels (LTHC) compared to high triglycerides/high cholesterol (HTHC) or low triglycerides/low cholesterol serum levels (LTLC). Collectively, these results suggest that the S protein interacts with the HDL particle and, depending on the lipid profile of the infected individual, it impairs its function during COVID-19 infection, causing an imbalance in lipid metabolism.

Deuteration for biological SANS: Case studies, success and challenges in chemistry and biology.

Small angle neutron scattering is a powerful complementary technique in structural biology. It generally requires, or benefits from, deuteration to achieve its unique potentials. Molecular deuteration has become a mature expertise, with deuteration facilities located worldwide to support access to the technique for a wide breadth of structural biology and life sciences. The sorts of problems well answered by small angle scattering and deuteration involve large (>10Å) scale flexible movements, and this approach is best used where high-resolution methods (crystallography, NMR, cryo-EM) leave questions unanswered. This chapter introduces deuteration, reviewing biological deuteration of proteins, lipids and sterols, and then steps through the ever-expanding range of deuterated molecules being produced by chemical synthesis and enabling sophisticated experiments using physiologically relevant lipids. Case studies of recent successful use of deuteration may provide illustrative examples for strategies for future experiments. We discuss issues of nomenclature for synthesised molecules of novel labeling and make recommendations for their naming. We reflect on our experiences, with cost associated with achieving an arbitrary deuteration level, and on the benefits of experimental co-design by user scientist, deuteration scientist, and neutron scattering scientist working together. Although methods for biological and chemical deuteration are published in the public domain, we recommend that the best method to deuterate is to engage with a deuteration facility.

Immunohistochemistry to detect hereditary nonpolyposis colorectal cancer in young patients: the 7-year Auckland experience.

BACKGROUND: In accordance with the Bethesda Guidelines, Auckland's metropolitan hospitals routinely perform immunohistochemistry for mismatch repair proteins on the tumor specimens of all patients with colorectal cancer aged 50 years and younger. When loss of expression is evident, patients are offered genetic counseling and gene mutation analysis. OBJECTIVES: This study aimed to determine the completeness of young patient capture over the first 7 years of routine testing, to find whether patients were referred for genetic testing, and to determine the proportion of patients found to have a mismatch repair gene mutation. DESIGN: This study retrospectively reviewed clinical, pathological, and genetic data. SETTINGS: The study was conducted at 3 public hospitals in Auckland, New Zealand. PATIENTS: All patients aged 50 years and younger treated for colorectal cancer at Auckland's metropolitan hospitals between January 2001 and December 2007 (n = 243) were included. MAIN OUTCOME MEASURES: The loss of expression of mismatch repair proteins by immunohistochemistry, referral for genetic testing, and proportion with mismatch repair gene mutation were the main outcome measures. RESULTS: Two hundred fourteen (88%) eligible patients had immunohistochemical analysis of their tumor and 33 (14%) had loss of expression of one or more mismatch repair proteins. Twenty-six patients were referred for genetic counseling, of whom 22 underwent genetic testing. A mismatch repair gene mutation was identified in 10 patients. LIMITATIONS: Seven patients with loss of expression of mismatch repair proteins by immunohistochemistry were not referred for genetic assessment. CONCLUSIONS: We have identified a mismatch repair gene mutation diagnostic of hereditary nonpolyposis colorectal cancer in 5% of all patients with colorectal cancer who were aged 50 years and younger. Routine immunohistochemical prescreening has important clinical benefit for these patients and their relatives.

The discovery of a potent and selective pyrazolo-[2,3-e]-[1,2,4]-triazine cannabinoid type 2 receptor agonist.

The development of selective CB2 receptor agonists is a promising therapeutic approach for the treatment of inflammatory diseases, without CB1 receptor mediated psychoactive side effects. Preliminary structure-activity relationship studies on pyrazoylidene benzamide agonists revealed the -ylidene benzamide moiety was crucial for functional activity at the CB2 receptor. A small library of compounds with varying linkage moieties between the pyrazole and substituted phenyl group has culminated in the discovery of a potent and selective pyrazolo-[2,3-e]-[1,2,4]-triazine agonist 19 (CB2R EC50 = 19 nM, CB1R EC50 > 10 µM). Docking studies have revealed key structural features of the linkage group that are important for potent functional activity.

An overview of late-stage functionalization in today's drug discovery.

Introduction: Late-stage functionalization (LSF) can introduce important chemical groups in the very last steps of the synthesis. LSF has the potential to speed up the preparation of novel chemical entities and diverse chemical libraries and have a major impact on drug discovery. Functional group tolerance and mild conditions allows access to new molecules not easily accessible by conventional approaches without the need for laborious de novo chemical synthesis. Areas Covered: A historical overview of late-stage functionalization and its applicability to drug discovery is provided. Pioneering methodologies that laid the foundations for the field are briefly covered and archetypal examples of their application to drug discovery are discussed. Novel methodologies reported in the past few years mainly stemming from the recent renaissances of photoredox catalysis and radical chemistry are reviewed and their application to drug discovery considered. Expert opinion: It is envisioned that late-stage functionalization will improve the efficiency and efficacy of drug discovery. There is evidence of the widespread uptake of LSF by the medicinal chemistry community and it is expected that the recent and continuing endeavors of many academic laboratories and pharmaceutical companies will soon have an impact on drug development.

Strategies to develop selective CB2 receptor agonists from indole carboxamide synthetic cannabinoids.

Activation of the CB2 receptor is an attractive therapeutic strategy for the treatment of a wide range of inflammatory diseases. However, receptor subtype selectivity is necessary in order to circumvent the psychoactive effects associated with activation of the CB1 receptor. We aimed to use potent, non-selective synthetic cannabinoids designer drugs to develop selective CB2 receptor agonists. Simple structural modifications such as moving the amide substituent of 3-amidoalkylindole synthetic cannabinoids to the 2-position and bioisosteric replacement of the indole core to the 7-azaindole scaffold are shown to be effective and general strategies to impart receptor subtype selectivity. 2-Amidoalkylindole 16 (EC50 CB1 > 10 µM, EC50 CB2 = 189 nM) and 3-amidoalkyl-7-azaindole 21 (EC50 CB1 > 10 µM, EC50 = 49 nM) were found to be potent and selective agonists with favourable physicochemical properties. Docking studies were used to elucidate the molecular basis for the observed receptor subtype selectivity for these compounds.

Haemorrhoid energy therapy versus rubber band ligation for the management of grade I and II haemorrhoids: a randomized trial.

BACKGROUNDS: Grade I and II haemorrhoids are commonly managed in colorectal practice. Management often involves rubber band ligation. The haemorrhoid energy therapy (HET) device (Medtronic, Minneapolis, MN, USA) has been developed as an alternative to rubber band ligation (RBL). This study is the first to prospectively evaluate the device versus RBL in the management of grade I and II haemorrhoids. METHODS: A single blind, randomized controlled trial was conducted in the colorectal outpatient department. Patients with symptomatic haemorrhoids suitable for banding were prospectively recruited and randomized. Primary outcome was post procedural pain at 1 h as recorded on a 10-point Likert scale. Secondary outcomes were efficacy in reduction of haemorrhoidal symptom score at 12 weeks, daily average and maximum pain scores for 14 days and complications arising from the intervention. RESULTS: Thirty patients were randomized (14 HET, 16 RBL). There was no significant difference between the two group's pre-intervention symptom score and haemorrhoidal grade. The mean pain scores at 1 h in the HET group were 1.5 ± 068 (95% confidence interval), and in the RBL group 4.64 ± 1.74 (95% confidence interval) (P < 0.05). Average (0.7 versus 2.95, P < 0.05) and maximum (1.25 versus 4.4, P < 0.05) pain were lower in the HET group on day one post procedure. At 12 weeks there was no significant difference in the reduction of haemorrhoid symptom scores between the groups (HET 2.27, RBL 1.5 (P > 0.2)). CONCLUSION: HET causes less pain then RBL, and is at least as effective in treating the symptoms associated with grade I and II haemorrhoids in the outpatient setting.

Acute and residual effects in adolescent rats resulting from exposure to the novel synthetic cannabinoids AB-PINACA and AB-FUBINACA.

Synthetic cannabinoids (SCs) have rapidly proliferated as recreational drugs, and may present a substantial health risk to vulnerable populations. However, information on possible effects of long-term use is sparse. This study compared acute and residual effects of the popular indazole carboxamide SC compounds AB-PINACA and AB-FUBINACA in adolescent rats with ∆9-tetrahydrocannabinol (THC) and control treatments. Albino Wistar rats were injected (i.p.) with AB-PINACA or AB-FUBINACA every second day (beginning post-natal day (PND) 31), first at a low dose (0.2 mg/kg on 6 days) followed by a higher dose (1 mg/kg on a further 6 days). THC-treated rats received equivalent doses of 6 × 1 mg/kg and 6 × 5 mg/kg. During drug treatment, THC, AB-PINACA, and AB-FUBINACA decreased locomotor activity at high and low doses, increased anxiety-like behaviours and audible vocalisations, and reduced weight gain. Two weeks after dosing was completed, all cannabinoid pre-treated rats exhibited object recognition memory deficits. These were notably more severe in rats pre-treated with AB-FUBINACA. However, social interaction was reduced in the THC pre-treated group only. Six weeks post-dosing, plasma levels of cytokines interleukin (IL)-1α and IL-12 were reduced by AB-FUBINACA pre-treatment, while cerebellar endocannabinoids were reduced by THC and AB-PINACA pre-treatment. The acute effects of AB-PINACA and AB-FUBINACA were broadly similar to those of THC, suggesting that acute SC toxicity in humans may be modulated by dose factors, including inadvertent overdose and product contamination. However, some lasting residual effects of these different cannabinoid receptor agonists were subtly different, hinting at recruitment of different mechanisms of neuroadaptation.

Palliative colonic stenting: a safe alternative to surgery in stage IV colorectal cancer.

BACKGROUND: The morbidity associated with surgery for obstructing or near-obstructing stage IV colorectal cancer can be high including the frequent need for a stoma. Self-expandable metal stents (SEMS) offer an alternative to surgery. Our aim was to analyse our palliative SEMS outcomes and compare this with a palliative surgery group. METHODS: A retrospective study of a single institutions' experience with SEMS or surgery in the management of stage IV colorectal cancer was performed. RESULTS: Sixty-five patients treated with SEMS were included in the study. These were compared with an unmatched group of 63 patients who underwent surgery. Within the SEMS group was a 98.5% technical success and 100% clinical success of deployed SEMS. Overall complication rate was low at 23.1% (restenosis 7.7%, migration 7.7%, perforation 4.6% and bleeding 3.1%). Only 7.7% of patients in the SEMS group required an operation. SEMS insertion was associated with a shorter hospital stay (2.9 days versus 14.6 days; P < 0.001) and reduced requirement for a stoma (4.6% versus 44.4%; P < 0.001). There was no statistically significant difference in 30-day mortality (13.8% versus 11.1%; P = 0.640), 1-year survival (42.9% versus 41.4%; P = 0.949) or 2-year survival (24.5% versus 21.4%; P = 0.700). Overall survival was equivalent between the two groups (hazard ratio 1.27; 95% confidence interval 0.88-1.88; P = 0.212). CONCLUSION: SEMS is a safe alternative to surgery in obstructing or near-obstructing stage IV colorectal cancer. It offers high success rate, a shorter hospital stay and a reduced stoma rate while not impacting overall survival.

Pharmacology of Indole and Indazole Synthetic Cannabinoid Designer Drugs AB-FUBINACA, ADB-FUBINACA, AB-PINACA, ADB-PINACA, 5F-AB-PINACA, 5F-ADB-PINACA, ADBICA, and 5F-ADBICA.

Synthetic cannabinoid (SC) designer drugs based on indole and indazole scaffolds and featuring l-valinamide or l-tert-leucinamide side chains are encountered with increasing frequency by forensic researchers and law enforcement agencies and are associated with serious adverse health effects. However, many of these novel SCs are unprecedented in the scientific literature at the time of their discovery, and little is known of their pharmacology. Here, we report the synthesis and pharmacological characterization of AB-FUBINACA, ADB-FUBINACA, AB-PINACA, ADB-PINACA, 5F-AB-PINACA, 5F-ADB-PINACA, ADBICA, 5F-ADBICA, and several analogues. All synthesized SCs acted as high potency agonists of CB1 (EC50 = 0.24-21 nM) and CB2 (EC50 = 0.88-15 nM) receptors in a fluorometric assay of membrane potential, with 5F-ADB-PINACA showing the greatest potency at CB1 receptors. The cannabimimetic activities of AB-FUBINACA and AB-PINACA in vivo were evaluated in rats using biotelemetry. AB-FUBINACA and AB-PINACA dose-dependently induced hypothermia and bradycardia at doses of 0.3-3 mg/kg, and hypothermia was reversed by pretreatment with a CB1 (but not CB2) antagonist, indicating that these SCs are cannabimimetic in vivo, consistent with anecdotal reports of psychoactivity in humans.

The colorectal cancer patients' journey: the Auckland region.

AIM: To identify the time taken from referral to first treatment of patients with colorectal cancer (CRC) in the Auckland region and benchmark these against available guidelines for timeliness. METHOD: Retrospective study of clinical records of all patients diagnosed with CRC identified from the national registry and Auckland regional databases in the years 2001 and 2005. Data extracted included demographics, dates and types of interventions and the patient journey from referral to initiation of first treatment. RESULTS: Of the 1128 patients diagnosed and treated in these cohorts, 68% were referred through their general practitioner and 58% saw a surgeon at their first specialist appointment. Seventy-nine percent received initial treatment with curative intent. The median time from initial referral to first treatment was 35 days, with only 68% of patients being treated within 62 days of initial referral. CONCLUSION: The colorectal patient journey is complicated by multiple pathways of presentation and treatment and by patient choice. These factors need to be considered when assessing the acceptability of transit times based on summary data. That nearly one-third of patients did not complete the United Kingdom-based target of 62 days from referral to first treatment indicates there is a need for further improvement in service delivery for patients developing CRC in the Auckland region.