Acute on chronic liver failure: A South Australian experience

Background and Aim

Acute on chronic liver failure (ACLF) is a clinical syndrome described in patients with acute decompensation (AD) of cirrhosis, characterized by organ failures and high mortality. Intensive management, including liver transplantation (LT), has been shown to improve survival. To address the limited Australian data on ACLF, we describe the prevalence, clinical profile, and outcome of ACLF in an Australian cohort of hospitalized patients.

Methods

A retrospective review of hepatology admissions in a tertiary hospital from 1 January 2017 to 31 December 2019 identified AD and ACLF cohorts, as defined by the European Association for Study of the Liver definition. Patient characteristics, clinical course, survival at 28- and 90-day survival, and feasibility of LT were analyzed.

Results

Among the 192 admissions with AD, 74 admissions (39%) met ACLF criteria. A prior diagnosis of alcohol-related cirrhosis was highly prevalent in both cohorts. Grade-1 ACLF was the most frequent (60%), with renal failure being the commonest organ failure; 28-day (23% vs 2%, P = <0.001) and 90-day mortality (36% vs 16%, P = 0.002) were higher in ACLF than AD. Due to ongoing alcohol use disorder (AUD), only six patients underwent LT assessment during ACLF admission.

Conclusion

ACLF was common in our cohort of cirrhosis with AD and was associated with high mortality. AUD despite prior cirrhosis diagnosis was a barrier to LT. Prioritization of ACLF patients for LT after addressing AUD and relaxation of the 6-month abstinence rule may improve ACLF survival and should be addressed in prospective studies.

General health complaints and sleep associated with new injury within an endurance sporting population: A prospective study

OBJECTIVES

To examine the association between subjective health complaints, sleep quantity and new injury within an endurance sport population.

DESIGN

Prospective cohort study.

METHODS

Ninety-five endurance sporting participants were recruited from running, triathlon, swimming, cycling and rowing disciplines. Over 52-week period participants submitted weekly data regarding subjective health complaints (SHCs) (cardiorespiratory, gastrointestinal and psychological/lifestyle), sleep quantity, training load and new injury episodes. Applying a 7- and 14-day lag period, a shared frailty model was used to explore new injury risk associations with total SHCs and sleep quantity.

RESULTS

92.6% of 95 participants completed all 52 weeks of data submission and the remainder of the participants completed ≥30 weeks. Seven-day lag psychological/lifestyle SHCs were significantly associated with new injury risk (Hazard ratio (HR)=1.32; CI 95%=1.01-1.72, p<0.04). In contrast, cardiorespiratory (HR=1.15; CI 95%=0.99-1.36, p=0.07) and gastrointestinal (HR=0.77; CI 95%=0.56-1.05, p=0.09) SHCs were not significantly associated with new injury risk. New injury risk had a significant increased association with 14-day lag <7h/day sleep quantity (HR=1.51; CI 95%=2.02-1.13, p<0.01) and a significant decreased association with >7h/day sleep quantity (HR=0.63, CI 95%=0.45-0.87, p<0.01. A secondary regression analysis demonstrated no significant association with total SHCs and training load factors (Relative Risk (RR)=0.08, CI 95%=0.04-0.21, p=0.20).

CONCLUSIONS

To minimise an increased risk of new injuries within an endurance sporting population, this study demonstrates that psychological/lifestyle subjective health complaints and sleep quantity should be considered. The study also highlights a lag period between low sleep quantity and its subsequent impact on new injury risk. No association was demonstrated between subjective health complaints, sleep quantity and training load factors.

Maternal adverse childhood experiences, mental health, and child behaviour at age 3: The all our families community cohort study

Links between adverse childhood experiences (ACEs) and threats to health and well-being later in life are well established. The current study extends those findings into younger populations of pregnant women and their children; investigating how ACEs relates to maternal postpartum well-being, coping, and parenting, as well as child outcomes. Participants included 1994 mothers and children from the All Our Families community-based cohort in Alberta, Canada, followed from pregnancy (from 2008 to 2011) until child age 3 years. The sample is representative of the pregnant population in an urban Canadian centre. Mothers completed questionnaires on ACEs, postpartum mental health, as well as parenting morale, efficacy, coping, and personality. Child outcomes included internalizing and externalizing behavior, as well as temperament. Approximately 62% of participants experienced at least one ACE; 25% experienced 3 or more ACEs. The presence of 3 or more ACEs was associated with postpartum smoking, binge drinking, depressive and anxiety symptoms, lower optimism and higher neuroticism, and lower reported parenting morale. In children, 3 or more maternal ACEs was associated with higher levels of internalizing (e.g., anxiety) and externalizing difficulties (aggression and hyperactivity), as well as temperament (surgency and negative affectivity). Cumulative maternal ACEs are associated with postpartum mental health and parenting morale, as well as maladaptive coping strategies. The demonstrated downstream consequences of maternal ACEs for child outcomes suggests that early intervention strategies and community resources to improve life course outcomes for parents and children are critical for breaking intergenerational continuities of risk.

Salmonella Oranienburg isolated from horses, wild turkeys and an edible home garden fertilized with raw horse manure

In July 2010, a horse from a rural farm (Farm A) in coastal Northern California was diagnosed with Salmonella Oranienburg infection following referral to a veterinary hospital for colic surgery. Environmental sampling to identify potential sources and persistence of Salmonella on the farm was conducted from August 2010 to March 2011. Salmonella was cultured using standard enrichment and selective plating. Pure colonies were confirmed by biochemical analysis, serotyped and compared by pulsed-field gel electrophoresis (PFGE) analysis. A total of 204 clinical and environmental samples at Farm A were analysed, and Salmonella spp. was isolated from six of eight (75%) horses, an asymptomatic pet dog, two of seven (28.6%) water samples from horse troughs, nine of 20 (45%) manure storage pile composites, 16 of 71 (22.5%) wild turkey faeces and four of 39 (10.3%) soil samples from the family's edible home garden. Well water and garden vegetable samples and horse faecal samples from a neighbouring ranch were negative. S. Oranienburg with a PFGE pattern indistinguishable from the horse clinical strain was found in all positive sample types on Farm A. The investigation illustrates the potential for widespread dissemination of Salmonella in a farm environment following equine infections. We speculate that a recent surge in the wild turkey population on the property could have introduced S. Oranienburg into the herd, although we cannot rule out the possibility wild turkeys were exposed on the farm or to other potential sources of Salmonella. Findings from the investigation indicated that raw horse manure applied as fertilizer was the most likely source of garden soil contamination. Viable S. Oranienburg persisted in garden soil for an estimated 210 days, which exceeds the 120-day standard between application and harvest currently required by the National Organic Program. The study underscores the need to educate the public about potential food safety hazards associated with using raw animal manure to fertilize edible home gardens.

Evaluation of a novel radiopacifiying agent on the physical properties of surgical spineplex

Polymethlylmethacrylate (PMMA) is the most frequently used cement for percutaneous vertebroplasty and kyphoplasty. To aid visualisation during surgery cements are doped with radiopacifying agents such as Barium sulphate (Ba(2)SO(4)) or Zirconium Dioxide (ZiO(2)). Mounting research suggests that these agents may impair the biocompatibility of the cements. However, incorporating an alternative radiopacifier agent with excellent biocompatibility would be a significant step forward. Bioactive radiopaque glasses incorporating elements such as strontium (Sr) and zinc (Zn), known to have beneficial and therapeutic effects on bone, are of great interest in this respect. In this study, the Ba(2)SO(4) of the commercially available Spineplex was incrementally replaced with a radiopaque therapeutic glass composition. The resulting effects on cement setting time, peak isotherm, ultimate compressive strength, Young's modulus (up to 30 days cement maturation) and radiopacity were evaluated. The substitution lead to an increase in cement setting time from 13.1 mins for Spineplex to 16.6-18.3 mins for the glass substituted cements. The peak exotherm during curing was reduced from 74 degrees C for Spineplex to a minimum of 51 degrees C for the fully substituted cement, indicating that reduced thermal necrosis in the in vivo setting is likely with these materials. Ultimate compressive strength and Young's modulus of each formulation showed no significant deterioration due to the substitution. Finally, the radiopacity of the substituted cements were reduced by up to a maximum of 18% in comparison to the control. However, the experimental formulations still maintained radiopacity equivalent to several millimetres of aluminium. As such the substituted cements had substantial equivalence to the Spineplex control. In order to assess the clinical relevance of these findings further investigation is warranted.

Comparison of an experimental bone cement with a commercial control, Hydroset

Glass polyalkenoate cements based on strontium calcium zinc silicate glasses (Zn-GPCs) and high molecular weight polyacrylic acids (PAA) (MW; 52,000-210,000) have been shown to exhibit mechanical properties and in vitro bioactivity suitable for arthroplasty applications. Unfortunately, these formulations exhibit working times and setting times which are too short for invasive surgical applications such as bone void filling and fracture fixation. In this study, Zn-GPCs were formulated using a low molecular weight PAA (MW; 12,700) and a modifying agent, trisodium citrate dihydrate (TSC), with the aim of improving the rheological properties of Zn-GPCs. These novel formulations were then compared with commercial self-setting calcium phosphate cement, Hydroset, in terms of compressive strength, biaxial flexural strength and Young's modulus, as well as working time, setting time and injectability. The novel Zn-GPC formulations performed well, with prolonged mechanical strength (39 MPa, compression) greater than both vertebral bone (18.4 MPa) and the commercial control (14 MPa). However, working times (2 min) and rheological properties of Zn-GPCs, though improved, require further modifications prior to their use in minimally invasive surgical techniques.

The effects of ingesting a carbohydrate-electrolyte beverage 15 minutes prior to high-intensity exercise performance

The aim of this study was to examine the effect of ingesting a commercially available carbohydrate-electrolyte (CHO-E) solution on strenuous exercise performance. Ten apparently healthy male volunteers (Mean +/- SD; age 20 +/- 2 yrs; height 178 +/- 7 cm; body mass 77 +/- 10 kg; estimated VO(2 max) 56 +/- 3 ml x kg(-1) x min(-1) completed three experimental trials in random order separated by a minimum of 7 days. For each trial, subjects consumed (8 ml x kg(-1) body mass) either a CHO-E solution (6% carbohydrate, 50 mg Na/500 ml), a non-CHO-E placebo, or no fluid, 15 minutes prior to exercise. The exercise involved intermittent shuttle (20 m apart) running for 1 hr followed by an incremental shuttle running test to exhaustion. Subjects displayed longer exercise times when the CHO-E solution was ingested compared with placebo or no fluid groups (exercise time to exhaustion - CHO-E 649 +/- 95 s, vs. placebo 601 +/- 83 s, vs. no fluid 593 +/- 107 s, P < 0.05). There was a main effect for time for specific gravity of urine (P < 0.05 vs. postexercise, pooled data) and body mass (P < 0.05 vs. postexercise, pooled data). The main finding from this investigation indicates that drinking a CHO-E solution 15 minutes prior to exercise improves performance. This study has practical implications for those sports where drinking during activity is restricted.

Influence of two changes in the composition of an acrylic bone cement on its handling, thermal, physical, and mechanical properties

This study is a contribution to the growing body of work on the influence of changes in the composition of an acrylic bone cement on various properties of the curing and cured material. The focus is on one commercially-available acrylic bone cement brand, Surgical Simplex P, and three variants of it and a series of properties, namely, setting time, maximum exotherm temperature, activation energy and frequency factor for the polymerization reaction, diffusion coefficient for the uptake of phosphate buffered saline, at 37 degrees C, ultimate compressive strength (UCS), plane-strain fracture toughness, fatigue life (under fully-reversed tension-compression stress), hardness (H) and elastic modulus (both determined using quasi-static nanoindentation), and the variation of the storage and loss moduli with frequency of the applied force in a dynamic nanoindentation test. It was found that (a) a 68% reduction in the volume of the activator, N,N dimethyl-4-toluidine, relative to the total volume of the liquid monomer (the amounts of all the constituents in the powder and of the hydroquinone in the liquid monomer remaining unchanged) led to, for example, a significant decrease in the rate of the polymerization reaction, at 37 degrees C (c') and a significant increase in H; and (b) the elimination of the pre-polymerized poly (methyl methacrylate) beads in the powder (the amounts of all the other powder constituents and those of the liquid monomer remaining unchanged) led to, for example, a significant drop in c' and a significant increase in UCS. Thus, these findings suggest a strategy for optimizing the composition of an acrylic bone cement.

Optimisation of the composition of an acrylic bone cement: application to relative amounts of the initiator and the activator/co-initiator in Surgical Simplex P

In cemented arthroplasties, the two-part self-curing acrylic bone cement is currently the only material used for anchoring the total joint replacement to the contiguous bone. In virtually all commercially available formulations of this cement, the agents used for the initiation and activation/co-initiation of the radical polymerisation reaction are benzoyl peroxide (BPO) and N, N dimethyl-para-toluidine (DMPT), respectively. There are no reports in the open literature on the rationale for the amounts of these and other constituents in the formulations of the cement. Given the concerns that have been raised in the literature regarding the effect of residual DMPT on the body, it is important to keep the starting amounts of BPO and DMPT as high and as low, respectively, as possible. In the present work, the focus is on the relative amounts of these two agents in the case of one widely used commercial formulation, Surgical Simplex(R) P. Thirty variants of this cement were formulated, covering three concentrations of the co-polymer/BPO (75%, 80%, and 85% of the mass of the powder) and DMPT amounts (ranging from 0.8 %v/v to 2.4% v/v.) The setting time (t(set)), the peak temperature reached during the cement polymerisation process (T(max)), and the ultimate compressive strength (UCS) of each of the formulations were determined in accordance with procedures specified in ISO 5833. A critical examination of all the results indicated that the optimum ratio of the concentration of the initiator (BPO embedded in the PMMA-sytrene co-polymer) to that of the activator/co-initiator (DMPT) in Surgical Simplex(R) P is 57.14 (80%w/w co-polymer + BPO per 1.4%v/v DMPT). The mean values of t(set), T(max), and UCS of this optimum formulation were determined to be 12.30 min, 68 degrees C, and 101 MPa, respectively, all of which are within the limits specified in ISO 5833. The commercially available formulation of this cement contains 2.5%v/v DMPT, while the optimum formulation, as found in the present work, has 44% less DMPT, which may translate to a smaller amount of residual DMPT that is available for elution into the periprosthetic tissue in a cemented arthroplasty, over the in vivo life of the joint replacement.

Retrieval latency and "at-risk" memories

Does retrieval latency reflect variations in the strength of associations in episodic memory? In three experiments, subjects were given a single study and test trial on each of five lists of 10 paired associates. Spoken recall latencies were measured. When the subjects were later given a second test, initial recall latency was systematically related to intertest retention--that is, the faster the initial correct recall of a pair, the more likely a pair was to be recalled at the second test. This effect occurred at retention intervals of 5 min, 30 min, and 24 h and was present in the data for individual subjects. The results are consistent with the classical view of latency as a measure of trace strength and stand in sharp contrast with results reported by Benjamin, Bjork, and Schwartz (1998) that showed that fast retrievals from semantic memory were more poorly retained than slower ones.

Ineffectiveness of visual distinctiveness in enhancing immediate recall

Glenberg (1984) and others have theorized that greater recency effects are obtained with auditory as opposed to visual presentation because of greater temporal distinctiveness of items in auditory sequences. We tested a number of ways of enhancing visual distinctiveness, including the use of color, spatial location, and minimized visual interference. None of the seven experiments provided any evidence of improved recall from enhanced visual distinctiveness. In particular, no increase in recency effects was obtained with increased distinctiveness. Additional analyses of pairwise dependency in recall across serial positions also failed to show any evidence of the near-independence of recall of the terminal item that characterizes recall of auditory sequences. Visual-perceptual distinctiveness does not get mapped in any simple way onto memorial distinctiveness in an immediate-serial-recall task.

Self-induced nystatin resistance in Dictyostelium discoideum

The cellular slime mold Dictyostelium discoideum is normally susceptible to the action of the polyene antibiotic nystatin. We describe conditions under which transient nystatin resistance can be induced in the absence of detectable changes in sterol composition. These results suggest that nystatin plays a positive role in promoting resistance to itself.

USE OF NYSTATIN-RESISTANT MUTATIONS IN PARASEXUAL GENETIC ANALYSIS IN DICTYOSTELIUM DISCOIDEUM

Nystatin-resistant mutations exhibit extreme sensitivity to 1.3 mm coumarin. The mutations fall into three complementation groups so it is possible to select for nonallelic mutations conferring sensitivity to coumarin by selection on nystatin-containing nutrient agar plates. Complementation between such coumarin-sensitive mutations allows the selection of diploids on coumarin-containing nutrient agar. Two of the nystatin resistance genes, nysB and nysC, have been mapped tentatively to the previously unmarked linkage group V.