The effect of dietary lysine and valine fed during lactation on sow and litter performance

Sows (98 first parity and 104 second parity) were used to determine the effects of dietary lysine and valine on lactation performance. Treatments were arranged in a 2 x 3 factorial with two levels of lysine (.80 or 1.20%) and three valine:lysine ratios (80, 100, or 120% of lysine). For all sows, increasing dietary lysine increased litter weaning weight (P < .001) and litter weight gain (P < .002) and reduced sow weight loss (P < .001). Litter weight gain tended (P = .22) to increase with increasing dietary valine, but the increase was not significant. Data were separated into two groups: sows that weaned 10 or more pigs and sows that weaned fewer than 10 pigs. For sows that weaned 10 or more pigs, litter weaning weight (P < .001) and litter weight gain (P < .001) increased and sow BW loss decreased (P < .001) when dietary lysine increased from .80 to 1.20%. For sows that weaned fewer than 10 pigs, increasing lysine had no effect (P < .77) on litter growth rate. For sows weaning 10 or more pigs, litter weaning weights (linear, P < .04; quadratic, P < .06) and litter weight gain increased (linear, P < .04; quadratic, P < .02) as dietary valine increased. For sows that weaned fewer than 10 pigs, maximum litter weight gain was observed at a valine:lysine ratio of 100% (quadratic, P < .13). These results demonstrate the need to increase dietary lysine and valine as litter weaning weights increase. High-producing sows that wean 10 or more pigs require increased dietary lysine and valine to maximize litter growth rate and minimize sow weight loss compared with sows weaning fewer than 10 pigs. The independent increases in litter weaning weights from adding lysine and valine suggest separate modes of action for these amino acids in high-producing sows.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Microbialites and global environmental change across the Permian-Triassic boundary: a synthesis

Permian-Triassic boundary microbialites (PTBMs) are thin (0.05-15 m) carbonates formed after the end-Permian mass extinction. They comprise Renalcis-group calcimicrobes, microbially mediated micrite, presumed inorganic micrite, calcite cement (some may be microbially influenced) and shelly faunas. PTBMs are abundant in low-latitude shallow-marine carbonate shelves in central Tethyan continents but are rare in higher latitudes, likely inhibited by clastic supply on Pangaea margins. PTBMs occupied broadly similar environments to Late Permian reefs in Tethys, but extended into deeper waters. Late Permian reefs are also rich in microbes (and cements), so post-extinction seawater carbonate saturation was likely similar to the Late Permian. However, PTBMs lack widespread abundant inorganic carbonate cement fans, so a previous interpretation that anoxic bicarbonate-rich water upwelled to rapidly increase carbonate saturation of shallow seawater, post-extinction, is problematic. Preliminary pyrite framboid evidence shows anoxia in PTBM facies, but interbedded shelly faunas indicate oxygenated water, perhaps there was short-term pulsing of normally saturated anoxic water from the oxygen-minimum zone to surface waters. In Tethys, PTBMs show geographic variations: (i) in south China, PTBMs are mostly thrombolites in open shelf settings, largely recrystallised, with remnant structure of Renalcis-group calcimicrobes; (ii) in south Turkey, in shallow waters, stromatolites and thrombolites, lacking calcimicrobes, are interbedded, likely depth-controlled; and (iii) in the Middle East, especially Iran, stromatolites and thrombolites (calcimicrobes uncommon) occur in different sites on open shelves, where controls are unclear. Thus, PTBMs were under more complex control than previously portrayed, with local facies control playing a significant role in their structure and composition.

Can we use ChatGPT for Mental Health and Substance Use Education? Examining Its Quality and Potential Harms

BACKGROUND

The use of generative artificial intelligence, more specifically large language models (LLMs), is proliferating, and as such, it is vital to consider both the value and potential harms of its use in medical education. Their efficiency in a variety of writing styles makes LLMs, such as ChatGPT, attractive for tailoring educational materials. However, this technology can feature biases and misinformation, which can be particularly harmful in medical education settings, such as mental health and substance use education. This viewpoint investigates if ChatGPT is sufficient for 2 common health education functions in the field of mental health and substance use: (1) answering users' direct queries and (2) aiding in the development of quality consumer educational health materials.

OBJECTIVE

This viewpoint includes a case study to provide insight into the accessibility, biases, and quality of ChatGPT's query responses and educational health materials. We aim to provide guidance for the general public and health educators wishing to utilize LLMs.

METHODS

We collected real world queries from 2 large-scale mental health and substance use portals and engineered a variety of prompts to use on GPT-4 Pro with the Bing BETA internet browsing plug-in. The outputs were evaluated with tools from the Sydney Health Literacy Lab to determine the accessibility, the adherence to Mindframe communication guidelines to identify biases, and author assessments on quality, including tailoring to audiences, duty of care disclaimers, and evidence-based internet references.

RESULTS

GPT-4's outputs had good face validity, but upon detailed analysis were substandard in comparison to expert-developed materials. Without engineered prompting, the reading level, adherence to communication guidelines, and use of evidence-based websites were poor. Therefore, all outputs still required cautious human editing and oversight.

CONCLUSIONS

GPT-4 is currently not reliable enough for direct-consumer queries, but educators and researchers can use it for creating educational materials with caution. Materials created with LLMs should disclose the use of generative artificial intelligence and be evaluated on their efficacy with the target audience.

Successful restoration of arteriovenous dialysis access patency after late intervention

Background

Arteriovenous dialysis access may be lost due to stenosis and thrombosis. Patency may be restored by thrombectomy or thrombolysis, but this is often not undertaken when the presentation is delayed. The success rate of delayed intervention is largely unknown.

Methods

In this single-centre study, we identified all instances of arteriovenous vascular access (VA) failure treated with angioplasty, thrombectomy or thrombolysis between August 2010 and July 2013. Patency rates immediately after intervention, and after 3 months, were assessed using multilevel mixed effects logistic regression.

Results

Sixty failures occurred in 41 accesses (38 patients). The access age at failure was 495 (316–888) days. Intervention was carried out after >48 h in 19 failures (32%). Immediate patency was achieved in 46 failures, of which 32 remained patent after 3 months. Delaying intervention increased the likelihood of achieving immediate patency (OR 0.55, 95% CI 0.31–1.0, P = 0.05). Having lost arteriovenous accesses previously increased the risk of immediate failure (OR 4.0, 95% CI 1.07–14.95, P = 0.04). There was no association between failure-to-intervention-time and 3-month patency rates (P = 0.23). Effect estimates did not differ between arteriovenous fistulae and synthetic arteriovenous grafts.

Conclusion

Delayed intervention for failed arteriovenous VA may result in superior early patency rates and yields equivalent 3-month patency rates.

Microbial response to limited nutrients in shallow water immediately after the end-Permian mass extinction

Previous work indicates that a variety of microbes bloomed in the oceans after the end-Permian faunal mass extinction, but evidence is sporadically documented. Thus, the nature and geographic distribution of such microbes and their associations are unclear, addressed in this study using a series of biomarker groups. On the basis of microbial biomarker records of the 2-methylhopane index, evidence is presented for cyanobacterial blooms in both the western and eastern Tethys Sea and in both shallow and deep waters, after the mass extinction. The enhanced relative abundance of C(28) (expressed by the C(28) /C(29) ratio of) regular steranes suggests a bloom of prasinophyte algae occurred immediately after the end-Permian faunal extinction, comparable with those observed in some other mass extinctions in Phanerozoic. Significantly, cyanobacteria and prasinophyte algae show a synchronized onset of bloom in the shallow water Bulla section, north Italy, inferring for the first time their coupled response to the biotic crisis and the associated environmental conditions. However, in Meishan of Zhejiang Province in south China, the bloom declined earlier than in Bulla. The association of increased 2-methylhopane index with a negative shift in the nitrogen isotope composition infers a scenario of enhanced nitrogen fixation by cyanobacteria immediately after the faunal mass extinction. N(2) fixation by cyanobacteria is here interpreted to have provided prasinophyte algae with ammonium in nutrient-limited shallow waters, and thus caused their associated blooms.

Impact of postoperative acute kidney injury in patients undergoing major gastrointestinal surgery on 1-year survival and renal outcomes: a national multicentre cohort study

BACKGROUND

The intermediate-term impact of acute kidney injury (AKI) in patients after major gastrointestinal and liver surgery has not been well characterized. This study aimed to evaluate the 1-year mortality rate and renal outcomes associated with postoperative AKI in a national prospective cohort.

METHODS

This prospective multicentre, observational cohort with 1-year postoperative follow-up included adults undergoing major gastrointestinal and liver surgery across the UK and Ireland between 23 September and 18 November 2015. AKI was defined according to Kidney Disease Improving Global Outcomes (KDIGO) criteria. The primary outcome was death at 1-year after surgery, and the secondary outcome was Major Adverse Kidney Events (MAKE-365). Cox proportionate and multilevel logistic regression were used to account for case mix.

RESULTS

Of 5745 patients across 173 centres, 1-year follow-up data was completed for 3504 patients (62.2 per cent, 126 centres), with attrition largely explained by centre non-participation (63.1 per cent). Some 13.6 per cent (475 of 3504) patients developed AKI by 7 days after surgery (stage 1: 9.2 per cent; stage 2/3: 4.3 per cent). At 1 year, 10.8 per cent (378 patients) experienced a MAKE-365 endpoint (303 patients had died, 61 had renal replacement therapy and 78 had renal dysfunction). Patients who experienced AKI by 7 days after surgery had a higher hazard of death at 1 year for KDIGO stage 1 (hazard ratio 1.50 (95 per cent c.i. 1.08 to 2.08), P = 0.016) and KDIGO stage 2/3 (hazard ratio 2.96 (95 per cent c.i. 2.02 to 4.33), P < 0.001). Both KDIGO stage 1 (odds ratio 2.09 (95 per cent c.i. 1.50 to 2.92), P < 0.001) and stage 2/3 (odds ratio 9.26 (95 per cent c.i. 6.31 to 13.59), P < 0.001) AKI were independently associated with MAKE-365.

CONCLUSION

AKI events within 7 days after gastrointestinal or liver surgery are associated with significantly worse survival and renal outcomes at 1 year.

Long acting beta-blockers in the twenty fourth hour

Fifteen mild to moderate hypertensives were submitted to exercise testing using a bicycle ergometer with a fixed load. Heart rate, blood pressure and ECG were recorded throughout 5 min exercise and 10 min recovery. Oxygen uptake was measured during the final minute of exercise and blood glucose estimation and serum drug levels assessed 5 min after recovery. The above measurements were made after exactly 24 h following seven days administration of 160 mg of long acting (L.A.) propranolol, 200 mg of sustained action (S.A.) metoprolol and two matched placebos. Propranolol L.A. was superior to Metoprolol S.A. in the reduction of exercise induced tachycardia and both drugs were significantly superior to placebos. Both drugs were effective agents for the lowering of resting blood pressure after 24 h but propranolol L.A. was more effective in the lowering of systolic peaks observed during exercise. There was no significant effect upon oxygen uptake and blood glucose. The incidence of side effects was low and showed no significant difference from placebo.

Media reporting on alcohol and other drugs in Australia and the Mindframe guidelines: Baseline data

INTRODUCTION

The aim of this study was to generate a baseline database of print media reporting on alcohol and other drug (AOD) issues prior to the release of the Mindframe guidelines in March 2019. Specifically, to: (i) describe the content associated with media entries that focus on AOD use in Australian news media; (ii) determine how the media entries compare to several domains associated with recently developed Mindframe guidelines for publicly reporting on AOD; and (iii) identify content factors associated with different scores.

METHODS

Media entries between July 2016 and June 2017 were searched for key AOD-related terms using the Australian and New Zealand Newsstream database. Two coding schemes were developed to rate a stratified sample of 50% of the media entries against the Mindframe guidelines. Associations between content and total comparison scores were determined using linear regression models.

RESULTS

Detailed coding of the 2007 articles identified as relevant for the current study indicated that a majority (67%) were focused on one of three substances: alcohol, cannabis or methamphetamine. Most of the entries were either law enforcement (22%) or criminal justice related (19%). Entries that focused on methamphetamine scored significantly lower than entries on alcohol when compared to the Mindframe guidelines, similarly entries focused on crime/justice-related topics scored significantly lower than entries focused on positive outcomes.

DISCUSSION AND CONCLUSIONS

A disproportionate number of print media entries, particularly those related methamphetamine use, focused on crime or justice-related topics, potentially further contributing to stigma, and emphasising the legal consequences of AOD use.

Cracks in the ice: a digital health initiative disseminating evidence-based information about ‘ice’

Background

Crystal methamphetamine (‘ice') causes significant societal harm and attracts a high level of concern in Australia. Cracks in the Ice (CITI: cracksintheice.org.au) is a digital public health initiative that was developed as part of a national response to concerns about ice. CITI is the first centralised national online portal for evidence-based information and resources about ice in Australia. It provides targeted information and resources for health workers, people who use ice, their family and friends, community groups and schools. CITI was developed collaboratively with input from drug and alcohol experts and over 500 Australian community members, including people with lived experience. A national online survey was conducted to evaluate whether CITI is meeting the needs of the Australian community.

Methods

Eligible participants were Australian residents aged 18 years and over, and were recruited via the CITI website, email direct marketing, and social media. The survey assessed participants' perceptions of CITI (e.g., usability, navigation, utility) and their knowledge and attitudes about ice.

Results

2110 participants completed the survey, including people who use ice, affected family members, health workers, and general community members. Participants' response to CITI was overall positive and their knowledge of ice was generally good, but many held negative or stigmatising attitudes towards ice and people who use it.

Conclusions

Digital public health initiatives stand to overcome structural, geographical, and attitudinal barriers to alcohol and other drug (AOD) prevention efforts. CITI ensures evidence-based information about the drug ice is readily available across all of Australia. Community evaluations have shown that CITI is meeting the needs of the Australian community.

Key messages

Crystal methamphetamine (‘ice’) attracts a high level of concern in Australia. CITI is the first centralised national online portal for evidence-based information and resources about ice. Digital health initiatives stand to overcome structural, geographical, and attitudinal barriers to AOD prevention. Community evaluations ensure these initiatives meet the needs of their end-users.

Motherhood and Drinking: The Relative Importance of Mental Health and Psychosocial Factors on Maternal Alcohol Misuse During the Postpartum Period

OBJECTIVE

Being a mother of a young child may be protective against alcohol misuse for some, but not all, women. This is the first study to identify the mental health and psychosocial correlates of alcohol misuse among postpartum mothers.

METHOD

Mothers with a child younger than 12 months (n = 319) were recruited via social media to complete a cross-sectional online survey. Two hierarchical logistic regressions examined unique factors associated with heavy episodic drinking and hazardous alcohol use, including sociodemographic, poor mental health, and psychosocial factors.

RESULTS

On average, mothers drank alcohol at low levels (4 drinking days, nine standard drinks in the past month). One in 10 (11.6%) reported heavy episodic drinking during this time, and 1 in 12 (8.5%) were drinking at hazardous or greater levels. In the final models, older age and more severe postpartum anxiety were associated with a higher likelihood of hazardous drinking (odds ratio [OR] = 1.37, 1.09, respectively), whereas breastfeeding was associated with lower odds of heavy episodic drinking (OR = 0.29). Greater perceived social support was associated with lower odds of heavy episodic (OR = 0.56) and hazardous (OR = 0.39) drinking, whereas higher coping-with-anxiety and social-drinking motives were associated with greater odds of both forms of alcohol misuse (ORs = 3.51-10.40). Conformity drinking motives (e.g., drinking to avoid social rejection) were negatively associated with heavy episodic drinking (OR = 0.24).

CONCLUSIONS

Maternal anxiety, coping-with-anxiety and social-drinking motives, and reduced social support are important factors associated with postpartum alcohol misuse. These modifiable factors are potential targets for screening and intervention for mothers who may need additional support and preventative care.

Dacrocystitis

In clinical photography, two views are often better than one to maximise the amount of information available to the viewer. Photographers should not endeavour to record everything in one shot.

Co-design of digital public health substance use resources: A collaboration between young people and experts

ISSUE ADDRESSED

Substance use and mental illness remain critical issues for young Australians, however, engagement with evidence-based health resources is challenging among this age group. This study aimed to develop engaging, useful digital health resources, underpinned by neuroscience principles, to build awareness of the harms of electronic cigarettes (e-cigarettes) and concurrent alcohol and antidepressant use.

METHODS

A mixed-methods approach was adopted to co-design two evidence-based videos resources. The resources were co-designed with the Matilda Centre's Youth Advisory Board Centre's Youth Advisory Board through a series focus groups and individual feedback reviews. Young people residing in New South Wales were then invited to complete a survey to evaluate the usefulness, relatability and impact on perceived harms associated with each substance pre- and post-viewing resources.

RESULTS

A total of 100 participants completed the survey (mean age = 21.5 years, SD = 2.77, 42% Female, 2% Non-binary). The animated videos were well received, with the large majority (91% and 87% respectively) of participants rating them 'excellent' or 'very good'. After viewing the videos, there was a significant increase in the perception of harm associated with e-cigarette use, monthly (t(99) = 2.76, p = .003), weekly (t(99) = 4.82, p < .001) and daily (t(99) = 4.92, p < .001), and consuming alcohol whilst taking antidepressants both weekly (t(100) = 2.93, p = .004) and daily (t(100) = 3.13, p = .002).

CONCLUSIONS

This study describes a successful co-design process demonstrating how meaningful involvement of young people, alongside traditional research methods, can produce substance use prevention resources that are useful, engaging and increase knowledge of harms among young people. SO WHAT?: To achieve meaningful public health impact researchers, experts and digital creators can work together to co-create substance use educational materials that are engaging, well-liked, while imparting important health knowledge.