The Involvement of oxytocin in the subthalamic nucleus on relapse to methamphetamine-seeking behaviour

The psychostimulant methamphetamine (METH) is an addictive drug of abuse. The neuropeptide oxytocin has been shown to modulate METH-related reward and METH-seeking behaviour. Recent findings implicated the subthalamic nucleus (STh) as a key brain region in oxytocin modulation of METH-induced reward. However, it is unclear if oxytocin acts in this region to attenuate relapse to METH-seeking behaviour, and if this action is through the oxytocin receptor. We aimed to determine whether oxytocin pretreatment administered into the STh would reduce reinstatement to METH use in rats experienced at METH self-administration, and if this could be reversed by the co-administration of the oxytocin receptor antagonist desGly-NH2,d(CH2)5[D-Tyr2,Thr4]OVT. Male Sprague Dawley rats underwent surgery to implant an intravenous jugular vein catheter and bilateral microinjection cannulae into the STh under isoflourane anaesthesia. Rats were then trained to self-administer intravenous METH (0.1 mg/kg/infusion) by lever press during 2-hour sessions under a fixed ratio 1 schedule for 20 days. Following extinction of lever press activity, the effect of microinjecting saline, oxytocin (0.2 pmol, 0.6 pmol, 1.8 pmol, 3.6 pmol) or co-administration of oxytocin (3.6 pmol) and desGly-NH₂,d(CH₂)₅[D-Tyr²,Thr⁴]OVT (3 nmol) into the STh (200 nl/side) was examined on METH-primed reinstatement (1 mg/kg; i.p.). We found that local administration of the highest oxytocin dose (3.6 pmol) into the STh decreased METH-induced reinstatement and desGly-NH2,d(CH2)5[D-Tyr2,Thr4]OVT had a non-specific effect on lever press activity. These findings highlight that oxytocin modulation of the STh is an important modulator of relapse to METH abuse.17 page(s

Effects of oxytocin, cocktail, or vehicle microinjection in the STh on a. active lever presses, b. inactive lever presses, and c. locomotor activity during METH (1mg/kg, i.p.) primed reinstatement sessions (n = 8).

<p>All animals were exposed to each treatment condition in a counterbalanced manner # p < 0.05 vs. saline + METH condition; ** p < 0.01 vs prior extinction day. Data are presented as mean ± SEM.</p

Anatomical coronal diagrams depicting the microinjection sites in the STh.

<p>The coronal diagram on the left shows the injection sites for experiment one, and the diagram on the right shows the injection sites for experiment two. The numbers to the left of the image depict the distance in mm from bregma.</p

Mean (± SEM) number of a. infusions, b. active and inactive lever presses, as well as c. mean (± SEM) locomotor activity across the 20 days of intravenous METH (0.1mg/kg) self-administration and extinction.

<p>Extinction was conducted for a minimum of 10 days and until less than 25 lever presses were made per session for two consecutive days. Only the data from the first 10 days of extinction is displayed in comparison to the mean of the last three days of self-administration.</p

Diagnosis of colorectal and emergency surgical site infections in the era of enhanced recovery: an all-Wales prospective study

Aim Surgical site infections (SSIs) are associated with increased morbidity, hospital stay and cost. The literature reports that 25% of patients who undergo colorectal surgical procedures develop a SSI. Due to the enhanced recovery programme, patients are being discharged earlier with some SSIs presenting in primary care, making accurate recording of SSIs difficult. The aim of this study was to accurately record the 30-day SSI rate after surgery performed by colorectal surgeons nationally within Wales. Method During March 2019, a national prospective snapshot study of all patients undergoing elective or emergency colorectal and general surgical procedures under the care of a colorectal consultant at 12 Welsh hospitals was completed. There was a multimodal 30-day follow-up using electronic records, clinic visits and/or telephone calls. Diagnosis of SSI was based on Centers for Disease Control and Prevention diagnostic criteria. Results Within Wales, of the 545 patients included, 13% developed a SSI within 30 days, with SSI rates of 14.3% for elective surgery and 11.7% for emergency surgery. Of these SSIs, 49.3% were diagnosed in primary care, with 28.2% of patients being managed exclusively in the community. There were two peaks of diagnosis at days 5–7 and days 22–28. SSI rates between laparoscopic (8.6%) and open (16.2%) surgeries were significantly different (p = 0.028), and there was also a significantly different rate of SSI between procedure groups (p = 0.001), with high SSI rates for colon (22%) and rectal (18.9%) surgery compared with general surgical procedures. Conclusion This first all-Wales prospective study demonstrated an overall SSI rate of 13%. By incorporating accurate primary care follow-up it was found that 49.3% of these SSIs were diagnosed in primary care

Effect of Amoxicillin dose and treatment duration on the need for antibiotic re-treatment in children with Community-Acquired Pneumonia: The CAP-IT randomized clinical trial

Importance: The optimal dose and duration of oral amoxicillin for children with community-acquired pneumonia (CAP) are unclear. Objective: To determine whether lower-dose amoxicillin is noninferior to higher dose and whether 3-day treatment is noninferior to 7 days. Design, Setting, and Participants: Multicenter, randomized, 2 × 2 factorial noninferiority trial enrolling 824 children, aged 6 months and older, with clinically diagnosed CAP, treated with amoxicillin on discharge from emergency departments and inpatient wards of 28 hospitals in the UK and 1 in Ireland between February 2017 and April 2019, with last trial visit on May 21, 2019. Interventions: Children were randomized 1:1 to receive oral amoxicillin at a lower dose (35-50 mg/kg/d; n = 410) or higher dose (70-90 mg/kg/d; n = 404), for a shorter duration (3 days; n = 413) or a longer duration (7 days; n = 401). Main Outcomes and Measures: The primary outcome was clinically indicated antibiotic re-treatment for respiratory infection within 28 days after randomization. The noninferiority margin was 8%. Secondary outcomes included severity/duration of 9 parent-reported CAP symptoms, 3 antibiotic-related adverse events, and phenotypic resistance in colonizing Streptococcus pneumoniae isolates. Results: Of 824 participants randomized into 1 of the 4 groups, 814 received at least 1 dose of trial medication (median [IQR] age, 2.5 years [1.6-2.7]; 421 [52%] males and 393 [48%] females), and the primary outcome was available for 789 (97%). For lower vs higher dose, the primary outcome occurred in 12.6% with lower dose vs 12.4% with higher dose (difference, 0.2% [1-sided 95% CI -∞ to 4.0%]), and in 12.5% with 3-day treatment vs 12.5% with 7-day treatment (difference, 0.1% [1-sided 95% CI -∞ to 3.9]). Both groups demonstrated noninferiority with no significant interaction between dose and duration (P =.63). Of the 14 prespecified secondary end points, the only significant differences were 3-day vs 7-day treatment for cough duration (median 12 days vs 10 days; hazard ratio [HR], 1.2 [95% CI, 1.0 to 1.4]; P =.04) and sleep disturbed by cough (median, 4 days vs 4 days; HR, 1.2 [95% CI, 1.0 to 1.4]; P =.03). Among the subgroup of children with severe CAP, the primary end point occurred in 17.3% of lower-dose recipients vs 13.5% of higher-dose recipients (difference, 3.8% [1-sided 95% CI, -∞ to10%]; P value for interaction =.18) and in 16.0% with 3-day treatment vs 14.8% with 7-day treatment (difference, 1.2% [1-sided 95% CI, -∞ to 7.4%]; P value for interaction =.73). Conclusions and Relevance: Among children with CAP discharged from an emergency department or hospital ward (within 48 hours), lower-dose outpatient oral amoxicillin was noninferior to higher dose, and 3-day duration was noninferior to 7 days, with regard to need for antibiotic re-treatment. However, disease severity, treatment setting, prior antibiotics received, and acceptability of the noninferiority margin require consideration when interpreting the findings. Trial Registration: ISRCTN Identifier: ISRCTN76888927

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally