IRAK3 modulates downstream innate immune signalling through its guanylate cyclase activity

Interleukin-1 receptor associated kinase 3 (IRAK3) is a cytoplasmic homeostatic mediator of inflammatory responses and is potentially useful as a prognostic marker in inflammation. IRAK3 inhibits signalling cascades downstream of myddosome complexes associated with toll like receptors. IRAK3 contains a death domain that interacts with other IRAK family members, a pseudokinase domain and a C-terminus domain involved with tumour necrosis factor receptor associated factor 6 (TRAF6). Previous bioinformatic studies revealed that IRAK3 contained a guanylate cyclase centre in its pseudokinase domain but its role in IRAK3 action is unresolved. We demonstrate that wildtype IRAK3 is capable of producing cGMP. Furthermore, we show that a specific point mutation in the guanylate cyclase centre reduced cGMP production. Cells containing toll like receptor 4 and a nuclear factor kappa-light-chain-enhancer of activated B cells (NFĸB) reporter system were transfected with IRAK3 or mutant IRAK3 proteins. Cell-permeable cGMP treatment of untransfected control cells suppresses downstream signalling through modulation of the NFĸB in the presence of lipopolysaccharides. Cells transfected with wildtype IRAK3 also suppress lipopolysaccharide induced NFĸB activity in the absence of exogenous cGMP. Lipopolysaccharide induced NFĸB activity was not suppressed in cells transfected with the IRAK3 mutant with reduced cGMP-generating capacity. Whereas in the presence of exogenously applied cell-permeable cGMP the IRAK3 mutant was able to retain its function by suppressing lipopolysaccharide induced NFĸB activity. Furthermore, increasing the amount of membrane permeable cGMP did not affect IRAK3's ability to reduce NFĸB activity. These results suggest that cGMP generated by IRAK3 may be involved in regulatory function of the protein where the presence of cGMP may selectively affect downstream signalling pathway(s) by modulating binding and/or activity of nearby proteins that interact in the inflammatory signalling cascade.

The relational dimensions of pharmaceutical care: Experience from caring for HIV-infected asylum seekers in Montréal

By describing the experience from dispensing antiretroviral drugs to asylum seekers infected with HIV in Montreal we argue for the relational dimensions of pharmaceutical care. Between 2010 and 2016, the Government of Canada changed the medical coverage for refugees and asylum seekers, leading to some uncertainty about what types of care were reimbursable for each migrant status. In Quebec, despite the compensatory coverage provided by the provincial medical insurance board (Régie d'assurance maladie du Québec, or RAMQ), this uncertainty led to a breakdown in patient followup in some establishments. The McGill University Health Centre's Chronic Viral Illness Service (CVIS) was nevertheless able to maintain continuity of care for refugees and asylum seekers living with HIV. This article looks more specifically at the pharmaceutical care provided during this period and, more particularly, at the convergence of the technical and relational dimensions. The methodology used was a qualitative case study, which made it possible to explore pharmaceutical care, by conducting qualitative interviews (n = 16). Semistructured interviews were conducted with patients and various professionals from the CVIS, including pharmacists. The cultural, administrative, and political dimensions of pharmaceutical care described here appear very important for overall patient care. Further reflection on the importance of relational dimensions of pharmaceutical care and the place and value of pharmaceutical care in the advancement of patient care is required.

A randomized controlled trial of an emollient with ceramide and filaggrin-associated amino acids for the primary prevention of atopic dermatitis in high-risk infants

BACKGROUND

Skin barrier dysfunction may precede infantile development of clinical atopic dermatitis (AD). Early-life emollient therapy to enhance barrier function may prevent or modify AD development in high-risk infants.

OBJECTIVES

(a) To determine whether daily full-body application of an emollient with ceramide and amino acids (study emollient) can reduce the cumulative AD incidence compared to standard skin care at 1 year of age. (b) To evaluate the study emollient's effect on skin barrier function, natural moisturizing factor and the microbiome using non-invasive biophysical and biochemical techniques.

METHODS

We performed a single-centre, investigator-blinded, randomized controlled trial enrolling infants at high risk for AD development determined by family history. The intervention was full-body once-daily application of the study emollient. The control arm was asked to not apply full-body emollient regularly and only use an emollient of their choice for dry skin. The primary outcome was the cumulative incidence of AD diagnosed at 12 months by a blinded investigator.

RESULTS

Less than half the target sample size was enrolled (n = 100, goal sample was 208) with 28% lost to follow-up. Across all clinical end points, a numerical trend was observed in favour of the intervention, although not statistically significant likely due to lack of power from under-enrolment. AD was diagnosed in 13.2% vs. 25.0% at 12 months (P = 0.204) and 19.4% vs. 31.0% at 2 years (P = 0.296) in intervention vs. control groups, respectively. There were no significant differences between groups in skin barrier or microbiome assessments. While there were no serious adverse events, there were more cases of reported contact dermatitis in the intervention vs. control arms, 9.3% vs. 4.3%, respectively; however, these events were not related to the study emollient and most mild in severity.

CONCLUSION

The observed trends suggest a protective effect of daily study emollient therapy compared to control.

The Geometric Effects on the Stress of Arterial Atherosclerotic Plaques: a Computational Study

BACKGROUND

The rupture of atherosclerotic plaques could cause serious clinical events. The wall shear stress (WSS) and axial plaque stress (APS) could reflect the risk of plaque rupture. This study aimed to quantitatively investigate the geometric effects on WSS and APS using computational fluid dynamics (CFD).

METHODS

63 plaque models were developed from three severities (75%, 82%, and 89% in area), three eccentricities (the deviation of plaque throat from the arterial centerline: 0, 0.375 and 0.75mm), and 7 different length combinations of the proximal and distal stenotic segments (2mm-5mm, 3mm-5mm, 4mm-5mm, 5mm-5mm, 5mm-4mm, 5mm-3mm, 5mm-2mm). For each model, CFD simulation was performed to calculate the maximum and area-averaged WSS and APS on the proximal and distal stenotic segments. The multivariate analysis of variance and linear regression analysis were performed to quantitatively investigate the geometry-stress relationship.The results showed that, the severity and eccentricity of a plaque were linearly related to its WSS and APS. APS value on a segment (proximal or distal) of the plaque depended on the segmental length It was also shown that the difference of APS between proximal and distal segments depended exclusively on the difference of length between segments (all p<; 0.05).

CONCLUSION

The geometry of a plaque influences its WSS and APS. APS and its proximal/distal difference depend on the segmental lengths.

MicroRNA from a 12-h versus 20-h acetylcysteine infusion for paracetamol overdose

Paracetamol overdose is common and microRNA (miR)-122 expression is increased with liver injury. We aimed to measure miR-122 in the setting of an abbreviated paracetamol overdose treatment regimen. We compared miRNA expression in patients treated for paracetamol poisoning with an abbreviated 12-h intravenous acetylcysteine regimen (200 mg/kg over 4 h, 50 mg/kg over 8 h) or a 20-h regimen (200 mg/kg over 4 h, 100 mg/kg over 16 h) (NACSTOP trial). miR-122 expression is increased (decreased cycle threshold (Ct) values) with paracetamol liver injury. We assessed miR-122 expression in patients receiving the two acetylcysteine regimens and in a separate group with acute liver injury (ALI). We examined 121 blood samples in 38 patients. After 20 h of acetylcysteine, median alanine transaminase (ALT) was 12 U/L (18, 14) versus 16 U/L (11, 21) ( p = 0.17) and median miR-122 Ct was 30.1 (interquartile range (IQR): 28.9, 33.3) versus 31.4 (28.9, 33.9) ( p = 0.7) in the NACSTOP abbreviated and control groups, respectively. Median normalized miR-122 Ct after 20 h of acetylcysteine was 2.2 (IQR 1.9, 6.4), 1.1 (0.7, 2.9), 63.9 (2.5, 168), 123.2 (40.9, 207.8) in the NACSTOP-abbreviated, NACSTOP-control, ALI and hepatotoxicity groups, respectively. There was no significant difference in ALT or miRNA between NACSTOP treatment groups and no signal of increased liver injury from an abbreviated 12-h acetylcysteine regimen. These findings suggest that an abbreviated acetylcysteine regimen in low-risk patients who have overdosed on paracetamol is safe. Further study is required to validate this finding utilizing miRNA as a comparative biomarker.

Trends in self-poisoning and psychotropic drug use in people aged 5-19 years: a population-based retrospective cohort study in Australia

OBJECTIVES

To characterise trends in self-poisoning and psychotropic medicine use in young Australians.

DESIGN

Population-based retrospective cohort study.

SETTING

Calls taken by the New South Wales and Victorian Poisons Information Centres (2006-2016, accounting for 70% of Australian poisoning calls); medicine dispensings in the 10% sample of Australian Pharmaceutical Benefits Scheme data (July 2012 to June 2016).

PARTICIPANTS

People aged 5-19 years.

MAIN OUTCOME MEASURES

Yearly trends in intentional poisoning exposure calls, substances taken in intentional poisonings, a prevalence of psychotropic use (dispensing of antidepressants, antipsychotics, benzodiazepines and medicines for attention deficit hyperactivity disorder (ADHD)).

RESULTS

There were 33 501 intentional poisonings in people aged 5-19 years, with an increase of 8.39% per year (95% CI 6.08% to 10.74%, p<0.0001), with a 98% increase overall, 2006-2016. This effect was driven by increased poisonings in those born after 1997, suggesting a birth cohort effect. Females outnumbered males 3:1. Substances most commonly taken in self-poisonings were paracetamol, ibuprofen, fluoxetine, ethanol, quetiapine, paracetamol/opioid combinations, sertraline and escitalopram. Psychotropic dispensing also increased, with selective serotonin reuptake inhibitors (SSRIs) increasing 40% and 35% July 2012 to June 2016 in those aged 5-14 and 15-19, respectively. Fluoxetine was the most dispensed SSRI. Antipsychotics increased by 13% and 10%, while ADHD medication dispensing increased by 16% and 10%, in those aged 5-14 and 15-19, respectively. Conversely, dispensing of benzodiazepines to these age groups decreased by 4% and 5%, respectively.

CONCLUSIONS

Our results signal a generation that is increasingly engaging in self-harm and is increasingly prescribed psychotropic medications. These findings indicate growing mental distress in this cohort. Since people who self-harm are at increased risk of suicide later in life, these results may foretell future increases in suicide rates in Australia.

The NACSTOP Trial: A Multicenter, Cluster-Controlled Trial of Early Cessation of Acetylcysteine in Acetaminophen Overdose

Historically, intravenous acetylcysteine has been delivered at a fixed dose and duration of 300 mg/kg over 20 to 21 hours to nearly every patient deemed to be at any risk for hepatotoxicity following acetaminophen overdose. We investigated a 12-hour treatment regimen for selected low-risk patients. This was a multicenter, open-label, cluster-controlled trial at six metropolitan emergency departments. We enrolled subjects following single or staggered acetaminophen overdose with normal serum alanine transaminase (ALT) and creatinine on presentation and at 12 hours, and less than 20 mg/L acetaminophen at 12 hours. Patients were allocated to intervention (250 mg/kg over 12-hour) or control (300 mg/kg over 20-hour) regimens by site. The primary outcome was incidence of "hepatic injury" 20 hours following initiation of acetylcysteine treatment, defined as ALT doubling and peak ALT greater than 100 IU/L, indicating the need for further antidotal treatment. Secondary outcomes included incidence of hepatotoxicity (ALT > 1,000 IU/L), peak international normalized ratio (INR), and adverse drug reactions. Of the 449 acetaminophen overdoses receiving acetylcysteine, 100 were recruited to the study. Time to acetylcysteine (median 7 hours [interquartile ratio 6,12] versus 7 hours [6,10]) and initial acetaminophen (124 mg/L [58,171] versus 146 mg/L [66,204]) were similar between intervention and control groups. There was no difference in ALT (18 IU/L [13,22] versus 16 IU/L [13,21]) or INR (1.2 versus 1.2) 20 hours after starting acetylcysteine between groups. No patients developed hepatic injury or hepatotoxicity in either group (odds ratio 1.0 [95% confidence interval 0.02, 50]). No patients represented with liver injury, none died, and 96 of 96 were well at 14-day telephone follow-up. Conclusion: Discontinuing acetylcysteine based on laboratory testing after 12 hours of treatment is feasible and likely safe in selected patients at very low risk of liver injury from acetaminophen overdose.

Large falcine meningioma presented as treatment-resistant depression: A case report

Large intracranial tumour may present only with psychiatric symptoms without any neurological deficits. Delay in surgical treatment may significantly affect the quality of life in these patients. We report a case of a young engineering student who was diagnosed as treatment-resistant depression without initial neuroimaging study. Further neuroimaging studies revealed he has a large falcine meningioma. His psychiatric symptoms resolved following surgical resection of the tumour. We emphasized the importance of initial neuroimaging study in young patients presenting with psychiatric symptoms.

Comparison of a Radiant Patient Warming Device with Forced Air Warming during Laparoscopic Cholecystectomy

The importance of maintaining a patient's core body temperature during anaesthesia to reduce the incidence of postoperative complications has been well documented. The standard practice of this institution is the use of a forced air device for intraoperative warming. The purpose of this study was to compare this standard with an alternative warming device using a radiant heat source which only heated the face.

This prospective, randomized controlled trial compared the efficacy of two methods of intraoperative warming: the BairHugger™ (Augustine Medical, U.S.A.) forced air device and the SunTouch™ (Fisher & Paykel Healthcare, N.Z.) radiant warmer during laparoscopic cholecystectomy in 42 female patients. Oesophageal core temperatures were recorded automatically on to computer during operations using standardised anaesthesia, intravenous infusions and draping.

The study failed to show any statistical or clinical difference between the two patient groups in terms of mean core temperature both intraoperatively (P=0.42) and in the recovery period (P=0.54). Mean start to end core temperature differences were marginly lower in the radiant group (0.08°C) but not statistically or clinically significantly different.

Given some of the drawbacks with forced air systems, such as the expense of the single use blanket, this new radiant warming device offers an alternative method of active warming with advantages in terms of cost and possible application to a wide variety of surgical procedures.

Does having a rotator cuff repair prior to reverse total shoulder arthroplasty influence the outcome?

Aims

The number of rotator cuff repairs that are undertaken is increasing. Reverse shoulder arthroplasty (RSA) is the procedure of choice for patients with rotator cuff arthropathy. We sought to determine whether patients who underwent rotator cuff repair and subsequent RSA had different outcomes compared with a matched control group who underwent RSA without a previous rotator cuff repair.

Patients and Methods

All patients with a history of rotator cuff repair who underwent RSA between 2000 and 2015 with a minimum follow-up of two years were eligible for inclusion as the study group. Outcomes, including the American Shoulder and Elbow Surgeons (ASES) scores, were compared with a matched control group of patients who underwent RSA without having previously undergone rotator cuff repair.

Results

The study group included 45 patients. Their mean age was 69 years (sd 8.6) and 27 patients (60%) were women. The mean ASES score improved from 43.1 to 76.6 two years postoperatively, and to 66.9 five years postoperatively. There was no significant difference between the outcomes at two years in the two groups (all p ≥ 0.05), although there was significantly more improvement in ASES scores in the control group (44.5 vs 33.4; p = 0.01). However, there was no significant difference between ASES scores at two and five years when baseline ASES scores were matched in the two groups (p = 0.42 at two years; p = 0.35 at five years).

Conclusion

Significant improvements in ASES scores were seen following RSA in patients who had previously undergone rotator cuff repair. They had higher baseline ASES scores than those who had not previously undergone this surgery. However, there was no significant difference in outcomes between the two groups, two years postoperatively. Previous rotator cuff repair does not appear to affect the early outcome after RSA adversely.

A RARE CASE OF OXYTOCIN-INDUCED MATERNAL CARDIAC BRADYARRHYTHMIA DURING LABOUR

The report a rare case of oxytocin-induced severe maternal bradyarrhythmia of a young healthy term primigravida with a singleton pregnancy in spontaneous labour. Augmentation of labour was initiated immediately following the diagnosis of poor progression of labour at four centimetres dilatation. An oxytocin infusion was administered as per standard hospital titration protocol. The patient developed ongoing, persistent episodes of severe bradycardia within six hours of commencement of the oxytocin infusion, as detected by routine pulse oximeter for maternal heart rate monitoring and confirmed manually. Oxytocin was ceased as soon this was recognised, and delivery was expedited by emergency caesarean section both for inadequate progress in labour and the inability to continue oxytocin infusion. Despite being theoretically known to cause cardiac arrhythmias, as a side effect, to our knowledge this is the first reported case in published literature of oxytocin-induced maternal bradycardia.