WNT5B drives osteosarcoma stemness, chemoresistance and metastasis

BACKGROUND

Treatment for osteosarcoma, a paediatric bone cancer with no therapeutic advances in over three decades, is limited by a lack of targeted therapies. Osteosarcoma frequently metastasises to the lungs, and only 20% of patients survive 5 years after the diagnosis of metastatic disease. We found that WNT5B is the most abundant WNT expressed in osteosarcoma tumours and its expression correlates with metastasis, histologic subtype and reduced survival.

METHODS

Using tumor-spheroids to model cancer stem-like cells, we performed qPCR, immunoblotting, and immunofluorescence to monitor changes in gene and protein expression. Additionally, we measured sphere size, migration and forming efficiency to monitor phenotypic changes. Therefore, we characterised WNT5B's relevance to cancer stem-like cells, metastasis, and chemoresistance and evaluated its potential as a therapeutic target.

RESULTS

In osteosarcoma cell lines and patient-derived spheres, WNT5B is enriched in stem cells and induces the expression of the stemness gene SOX2. WNT5B promotes sphere size, sphere-forming efficiency, and cell proliferation, migration, and chemoresistance to methotrexate (but not cisplatin or doxorubicin) in spheres formed from conventional cell lines and patient-derived xenografts. In vivo, WNT5B increased osteosarcoma lung and liver metastasis and inhibited the glycosaminoglycan hyaluronic acid via upregulation of hyaluronidase 1 (HYAL1), leading to changes in the tumour microenvironment. Further, we identified that WNT5B mRNA and protein correlate with the receptor ROR1 in primary tumours. Targeting WNT5B through inhibition of WNT/ROR1 signalling with an antibody to ROR1 reduced stemness properties, including chemoresistance, sphere size and SOX2 expression.

CONCLUSIONS

Together, these data define WNT5B's role in driving osteosarcoma cancer stem cell expansion and methotrexate resistance and provide evidence that the WNT5B pathway is a promising candidate for treating osteosarcoma patients.

KEY POINTS

WNT5B expression is high in osteosarcoma stem cells leading to increased stem cell proliferation and migration through SOX2. WNT5B expression in stem cells increases rates of osteosarcoma metastasis to the lungs and liver in vivo. The hyaluronic acid degradation enzyme HYAL1 is regulated by WNT5B in osteosarcoma contributing to metastasis. Inhibition of WNT5B with a ROR1 antibody decreases osteosarcoma stemness.

Arthroscopic Anatomic Reconstruction of the Anterior Talofibular and Calcaneofibular Ligaments Through a 2-Portal Technique

Arthroscopic anatomic lateral ligament reconstruction of the ankle joint has proven to be a safe option in the treatment of chronic ankle instability (CAI), with good functional results as well as allowing simultaneous management of associated lesions. We described an arthroscopic technique for anatomic reconstruction of the anterior talofibular ligament and calcaneofibular ligament using only 2 arthroscopic portals. This surgical technique to treat CAI is technically less demanding than other described techniques that use 3 or 4 arthroscopic portals. Moreover, as an anatomic technique, it has the advantage of preserving the biomechanics and kinematics of the ankle joint.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Pathology education project (PEP): A pilot program to spark student understanding in pathology as a career

According to the National Resident Matching Program in 2022, 631 pathology positions were offered. In total, 248 senior applicants from United States (US) allopathic schools filled 36.6% of these positions. To bolster medical student understanding of pathology, a medical school pathology interest group organized a multi-day activity to introduce rising second-year medical students to pathology as a career. Five students completed both pre- and post-activity surveys assessing their knowledge of the specialty. All five students had a BA/BS degree as their highest level of education. Only one student indicated that he or she had previously shadowed a pathologist as a medical laboratory scientist for a duration of four years. Two students indicated that they were interested in internal medicine, one indicated radiology, one forensic pathology or radiology, and one was undecided. During the activity, students biopsied tissue from cadavers in the gross anatomy lab. Thereafter, students participated in the standard tissue processing by shadowing a histotechnologist. Under the guidance of a pathologist, students microscopically examined slides and discussed the clinical findings. Post-activity survey results indicated that participation increased their knowledge of pathology as a career with a median increase of 0.8 points (range: 0.2 to 1.6) on a 5-point Likert scale. Students also indicated that their participation increased their knowledge of pathology skills and techniques-median increase of 1.2 (range: 0.8 to 1.8). This activity can be implemented by medical educators to expose medical students to pathology as a career with the benefit of increasing student knowledge in the specialty.

Increased Handpiece Speeds without Air Coolant: Aerosols and Thermal Impact

This study assessed the impact of increased speed of high-speed contra-angle handpieces (HSCAHs) on the aerosolization of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surrogate virus and any concomitant thermal impact on dental pulp. A bacteriophage phantom-head model was used for bioaerosol detection. Crown preparations were performed with an NSK Z95L Contra-Angle 1:5 (HSCAH-A) and a Bien Air Contra-Angle 1:5 Nova Micro Series (HSCAH-B) at speeds of 60,000, 100,000, and 200,000 revolutions per minute (rpm), with no air coolant. Bioaerosol dispersal was measured with Φ6-bacteriophage settle plates, air sampling, and particle counters. Heating of the internal walls of the pulp chambers during crown preparation was assessed with an infrared camera with HSCAH-A and HSCAH-B at 200,000 rpm (water flows ≈15 mL min^-1 and ≈30 mL min^-1) and an air-turbine control (≈23.5 mL min^-1) and correlated with remaining tissue thickness measurements. Minimal bacteriophage was detected on settle or air samples with no notable differences observed between handpieces or speeds (P > 0.05). At all speeds, maximum settled aerosol and average air detection was 1.00 plaque-forming units (pfu) and 0.08 pfu/m³, respectively. Irrespective of water flow rate or handpiece, both maximum temperature (41.5°C) and temperature difference (5.5°C) thresholds for pulpal health were exceeded more frequently with reduced tissue thickness. Moderate and strong negative correlations were observed based on Pearson's correlation coefficient, between remaining dentine thickness and either differential (r = -0.588) or maximum temperature (r = -0.629) measurements, respectively. Overall, HSCAH-B generated more thermal energy and exceeded more temperature thresholds compared to HSCAH-A. HSCAHs without air coolant operating at speeds of 200,000 rpm did not increase bioaerosolization in the dental surgery. Thermal risk is variable, dependent on handpiece design and remaining dentine thickness.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Dental Mitigation Strategies to Reduce Aerosolization of SARS-CoV-2

Limiting infection transmission is central to the safety of all in dentistry, particularly during the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Aerosol-generating procedures (AGPs) are crucial to the practice of dentistry; it is imperative to understand the inherent risks of viral dispersion associated with AGPs and the efficacy of available mitigation strategies. In a dental surgery setting, crown preparation and root canal access procedures were performed with an air turbine or high-speed contra-angle handpiece (HSCAH), with mitigation via rubber dam or high-volume aspiration and a no-mitigation control. A phantom head was used with a 1.5-mL min-1 flow of artificial saliva infected with Φ6-bacteriophage (a surrogate virus for SARS-CoV-2) at ~108 plaque-forming units mL-1, reflecting the upper limits of reported salivary SARS-CoV-2 levels. Bioaerosol dispersal was measured using agar settle plates lawned with the Φ6-bacteriophage host, Pseudomonas syringae. Viral air concentrations were assessed using MicroBio MB2 air sampling and particle quantities using Kanomax 3889 GEOα counters. Compared to an air turbine, the HSCAH reduced settled bioaerosols by 99.72%, 100.00%, and 100.00% for no mitigation, aspiration, and rubber dam, respectively. Bacteriophage concentrations in the air were reduced by 99.98%, 100.00%, and 100.00% with the same mitigations. Use of the HSCAH with high-volume aspiration resulted in no detectable bacteriophage, both on nonsplatter settle plates and in air samples taken 6 to 10 min postprocedure. To our knowledge, this study is the first to report the aerosolization in a dental clinic of active virus as a marker for risk determination. While this model represents a worst-case scenario for possible SARS-CoV-2 dispersal, these data showed that the use of HSCAHs can vastly reduce the risk of viral aerosolization and therefore remove the need for clinic fallow time. Furthermore, our findings indicate that the use of particle analysis alone cannot provide sufficient insight to understand bioaerosol infection risk.

Associations between preoperative anaemia and hospital costs following major abdominal surgery: cohort study

Background

Determining the cost-effectiveness and sustainability of patient blood management programmes relies on quantifying the economic burden of preoperative anaemia. This retrospective cohort study aimed to evaluate the hospital costs attributable to preoperative anaemia in patients undergoing major abdominal surgery.

Methods

Patients who underwent major abdominal surgery between 2010 and 2018 were included. The association between preoperative patient haemoglobin (Hb) concentration and hospital costs was evaluated by curve estimation based on the least-square method. The in-hospital cost of index admission was calculated using an activity-based costing methodology. Multivariable regression analysis and propensity score matching were used to estimate the effects of Hb concentration on variables related directly to hospital costs.

Results

A total of 1286 patients were included. The median overall cost was US $18 476 (i.q.r.13 784–27 880), and 568 patients (44.2 per cent) had a Hb level below 13.0 g/dl. Patients with a preoperative Hb level below 9.0 g/dl had total hospital costs that were 50.6 (95 per cent c.i. 14.1 to 98.9) per cent higher than those for patients with a preoperative Hb level of 9.0–13.0 g/dl (P < 0.001), 72.5 (30.6 to 128.0) per cent higher than costs for patients with a Hb concentration of 13.1–15.0 g/dl (P < 0.001), and 62.4 (21.8 to 116.7) per cent higher than those for patients with a Hb level greater than 15.0 g/dl (P < 0.001). Multivariable general linear modelling showed that packed red blood cell (PRBC) transfusions were a principal cost driver in patients with a Hb concentration below 9.0 g/dl.

Conclusion

Patients with the lowest Hb concentration incurred the highest hospital costs, which were strongly associated with increased PRBC transfusions. Costs and possible complications may be decreased by treating preoperative anaemia, particularly more severe anaemia.

Effects of treated wastewater irrigation on the establishment of young grapevines

Irrigation with treated wastewater could produce excessive accumulations within the plant and soil, negatively affecting the yield and production quality. In addition, the presence of biological and chemical contaminants could harm the agricultural environment, as well as the health of farmers and consumers. During this work, the suitability of secondary and tertiary treated wastewater for use in young grapevines was evaluated by studying the effect of the wastewater irrigation on the soil-plant system, crop yield, fruit quality and the presence of inorganic chemical contamination (salts, elements and heavy metals), organic chemical contamination (polycyclic aromatic hydrocarbons) and microbial contamination (E. coli, total coliforms). The results show that tertiary treated wastewater had positive impact on plant growth and yield while secondary treated wastewater had negative impact on fruit safety in comparison with tap water. Sodium levels in soils irrigated with treated wastewater increased at the end of the irrigation period while decreased during the wet season. The total polycyclic aromatic hydrocarbon concentrations in the soils ranged from 363 μg/kg to 374 μg/kg at the end of the experiment for all irrigation treatments applied. The use of tertiary treated wastewater was recommended for the irrigation of young grapevines as an alternative water source secured protection of environment, plant health and fruit quality.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

The development of lower-atmosphere turbulence early in a solar flare

We present the first observational study of the onset and evolution of solar flare turbulence in the lower solar atmosphere on an unprecedented time scale of 1.7 s using the Interface Region Imaging Spectrograph observing plasma at a temperature of 80,000 K. At this time resolution, nonthermal spectral line broadening, indicating turbulent velocity fluctuations, precedes the flare onset at this temperature and is coincident with net blue-shifts. The broadening decreases as the flare brightens and then oscillates with a period of ~10 s. These observations are consistent with turbulence in the lower solar atmosphere at the flare onset, heating that region as it dissipates. This challenges the current view of energy release and transport in the standard solar flare model, suggesting that turbulence partly heats the lower atmosphere.

Anterior Cruciate ligament injuries of the knee:

Abstract Background and problem statement Anterior cruciate ligament injuries are common among athletes and the general public. These injuries may lead to significant absence from activity with an associated financial and social burden. No definitive association has been described between mechanism of injury and pathology to enable us to put preventative measures in place in order to limit these injuries. Aim To determine whether there is an association between the mechanism of injury and the pathology seen on a magnetic resonance imaging (MRI) scan in anterior cruciate ligament (ACL) injuries. Methods This was a cross-sectional analytical study. Eighty seven male patients with an ACL injury, who had an MRI scan of the knee within the last two years participated in this study. Participants were contacted to give consent that their information be used in this study. The mechanism of injury and the pathology seen on the MRI scan was noted and categorised into different mechanism of injury groups and associated pathology groups. Statistical analyses included summaries of the data and a test for association between mechanism of injury and pathology. Since there were multiple pathology responses to each mechanism, a modified version of the chi-square test for independence was used. A 5% level of significance was specified. Results MRI scans of ACL injuries indicated that the mechanism of a solid foot plant with rotation of the knee has a greater tendency to be associated with medial meniscal injuries (77%), and also a 54% possibility to be associated with lateral meniscal injuries. A solid foot plant with a valgus stress on the knee showed a higher incidence of associated medial collateral ligaments (MCL) injuries (41%) and femoral bone bruising (62 %). These two mechanisms of injury are the most common in ACL injuries and contribute to the clinical significance found in this study. The p-value was however not statistically significant (p=0.44, chi-square value=20.27, df=45) for any association between pathology and mechanism of injury. Conclusion Some injury mechanisms causing ACL injury were more common than others and also had more associated pathology. The most common mechanism of injury noted is a solid foot plant with either rotation of the knee or valgus stress on the knee. Strengthening tissue structures involved in those movement patterns that cause these mechanisms can possibly limit ACL injuries in athletes and the general public.  Key words Anterior cruciate ligament injury, mechanism, association, pathology, MRI scan, prevention.

A cross-sectional study of 2550 amateur cyclists shows lack of knowledge regarding relevant sports nutrition guidelines

   Background: Amateur cyclists use a wide variety of supplements and nutritional substances to increase performance in addition to their training.  Objectives: The intended nutritional supplement use, carbohydrate (CHO) use and hydration practices of amateur cyclists before, during and after endurance cycling were analysed. Evidence of ignorance regarding the use of sports supplements and CHO, as well as the disregard of hydration strategy was hypothesised.  Methods: Amateur cyclists, of all age and sex groups, were requested to complete an online survey anonymously on the 2013 Momentum 94.7 Cycle Challenge website, a few days before the event.  Results: Responses were received from 2 550 out of 30 640 race entrants (8%); representing a distribution of 75% males, 25% females, with the majority between 25 to 45 years old. Nutritional supplements were used by 59% of respondents, with 77% dose adherence, and 29% with supplement ingredient knowledge. Half of the respondents (48%) planned to carbo-load two-three days before the event, while only five percent used professional advice to scientifically calculate their carbo-loading requirements. CHO were consumed by 81% during the event. Hydration preferences during the race were sports drinks (59%) and water (22%); and after the race 45% preferred a sports drink and 40% water. Ingredients, taste, colour, and temperature were criteria used to choose a sports drink. Only 18% of respondents knew to use both colour of urine and thirstiness to determine post-race fluid requirements.  Conclusion: The authors concluded that amateur cyclists had insufficient knowledge regarding nutritional supplement ingredients and usage, CHO requirements and carbo-loading practices, and hydration strategies before, during and after the event. 

On the Meteorites which have been found in the Desert of Atacama and its neighbourhood

The immediate object of the present paper is to place on record the history and characters of several Atacama meteorites of which no description has yet been published; but incidentally it is convenient at the same time to consider the relationship of these masses to others from the same region, which either have been already described, or at least are stated to be preserved in one or more of the known Meteorite-Collections.

On a Meteoric Iron found in 1884 in the Sub-district of Youndegin, Western Australia, and containing Cliftonite, a cubic form of Graphitic Carbon

This iron was found on January 5th, 1884, by Alfred Eaton, a mounted police constable, when on duty in the sub-district of Youndegin, at a spot distant about 60 chains (three-quarters of a mile) in a north-west direction from the top of Penkarring Rock, and roughly estimated by him as 70 miles east of York, Western Australia; this must be about longitude 117°30', E. of Greenwich, latitude 31°30' S. Only one of four observed fragments having been brought in by Mr. Eaton, the late Captain Smith, Commissioner of the Police at Perth, sent him out to Penkarring with a native assistant with instructions to bring in the other three, at the instance of the Rev. Charles G. Nicolay, Curator of the Geological Museum, Fremantle, to whomthe late Mr. Edward T. Hardman, F.C.S., the Government Geologist, had expressed his belief in the meteoric origin of the iron.

Significant OH production under surface cleaning and air cleaning conditions: Impact on indoor air quality

We report measurements of hydroxyl (OH) and hydroperoxy (HO₂ ) radicals made by laser-induced fluorescence spectroscopy in a computer classroom (i) in the absence of indoor activities (ii) during desk cleaning with a limonene-containing cleaner (iii) during operation of a commercially available "air cleaning" device. In the unmanipulated environment, the one-minute averaged OH concentration remained close to or below the limit of detection (6.5×10⁵  molecule cm^-3 ), whilst that of HO₂ was 1.3×10⁷  molecule cm^-3 . These concentrations increased to ~4×10⁶ and 4×10⁸  molecule cm^-3 , respectively during desk cleaning. During operation of the air cleaning device, OH and HO₂ concentrations reached ~2×10⁷ and ~6×10⁸  molecule cm^-3 respectively. The potential of these OH concentrations to initiate chemical processing is explored using a detailed chemical model for indoor air (the INDCM). The model can reproduce the measured OH and HO₂ concentrations to within 50% and often within a few % and demonstrates that the resulting secondary chemistry varies with the cleaning activity. Whilst terpene reaction products dominate the product composition following surface cleaning, those from aromatics and other VOCs are much more important during the use of the air cleaning device.

The prevalence, risk factors predicting injury and the severity of injuries sustained during competition in professional mixed martial arts in Africa

Background: Professional mixed martial arts (MMA) has gained international popularity. No African-based studies have reported the prevalence or severity of injuries, risk factors associated with injuries or return-to-play (RTP) time. Objectives: To determine the prevalence of injuries and associated risk factors, as well as severity of injuries sustained by professional male MMA athletes competing at the Extreme Fighting Championships Africa (EFC Africa) from 2010 to 2014.Methods: Permission to do the study and the medical records of all professional events (2010 – 2014) were obtained from EFC Africa. Data were obtained from 173 male competitors aged 18 to 44 years, who had participated in 300 professional MMA fights. Results from this prospective cohort study were compared to a similar study done in the United States of America (USA). An injury was defined as any damage to an athlete’s body that needed the attention of the ringside physician. Statistical analyses included descriptive statistics and a stepwise logistic regression. Odds of an injury were predicted with six independent variables: fight outcome, age, weight division, number of fights, injuries in the preceding fight and years of fighter experience.Results: Head, face and neck injuries were most common (22%), followed by traumatic brain injuries (knockouts) (6%). Losing a fight was a significant predictor of injury when using the stepwise logistic regression model (p=0.040). The odds ratio indicated that a preceding fight injury almost doubled the risk of injury in the following fight (OR 1.91; p= 0.163). Traumatic brain injuries (TBIs) in this study of African-based competitions (6%) were substantially higher than reported in the American study (1.8%).Conclusion: Head, neck and face injuries are common in African fighters. The high rate of TBIs in African competition compared to the USA study is concerning. This could reflect superior refereeing in the USA group, as fights may be ended sooner by stoppage. Further investigation of injury trends and preventative measures should be studied to reduce the incidence of injuries during African competitions.

The use of negative pressure wave treatment in athlete recovery

Background: Athletes need to recover fully to maximise performance in competitive sport. Athletes who replenish more quickly and more efficiently are able to train harder and more intensely. Elite athletes subjectively report positive results using lower body negative pressure (LBNP) treatment as an alternate method for rapid recovery, restoring and improving their impaired physical state. Objective data on the efficacy are lacking.Objectives: To investigate the effect of intermittent vacuum therapy on accelerating acute recovery following an athlete’s normal daily training schedule of strenuous exercise. Objective measurements of biological markers of muscular fatigue were used to assess recovery.Methods: Twenty-two male cricket players in a randomised cross-over study were divided into a treatment and control group respectively. Following a one-hour high-intensity gym session, the treatment group received three 30-minute LBNP exposure sessions over three consecutive days (0, 24 and 48 hours). Blood lactate and creatine kinase biomarkers were collected to measure the recovery process. After 14 days groups were crossed over and the trial repeated.Results: Heart rate and blood pressure decreased noticeably during treatment, reverting to baseline levels after treatment. Lactate concentrations decreased in both groups after exercise termination; significantly more in the treatment (0.57±0.23 mmol/l) than control group (0.78±0.22 mmol/l), p<0.001). Creatine kinase (CK) was similar in both groups. Athletes’ subjective assessments of recovery rated moderately high.Conclusion: LBNP therapy applied as treatment during routine schedule may have a systemic effect in lowering serum lactate levels, but not CK levels. Enhanced recovery of athletes is still unconfirmed.

X-ray scattering measurements of dissociation-induced metallization of dynamically compressed deuterium

Hydrogen, the simplest element in the universe, has a surprisingly complex phase diagram. Because of applications to planetary science, inertial confinement fusion and fundamental physics, its high-pressure properties have been the subject of intense study over the past two decades. While sophisticated static experiments have probed hydrogen's structure at ever higher pressures, studies examining the higher-temperature regime using dynamic compression have mostly been limited to optical measurement techniques. Here we present spectrally resolved x-ray scattering measurements from plasmons in dynamically compressed deuterium. Combined with Compton scattering, and velocity interferometry to determine shock pressure and mass density, this allows us to extract ionization state as a function of compression. The onset of ionization occurs close in pressure to where density functional theory-molecular dynamics (DFT-MD) simulations show molecular dissociation, suggesting hydrogen transitions from a molecular and insulating fluid to a conducting state without passing through an intermediate atomic phase.

Physical activity of children from a small rural town, South Africa

Introduction: Physical activity plays an integral role in the normal physical, mental, social and cognitive development of children. One of the main reasons for overweight children in low- and middle-income countries like South Africa is inactivity. This study’s aim was to describe the physical activity measured in boys and girls from section 21, quintile 5 pre-primary and primary schools in a small rural South African town and to compare it with recommended international physical activity levels.Method: Seventy-eight rural children, representing Caucasian and black African children, divided into three age groups, were issued a piezoelectric pedometer for seven complete days. Pedometer data obtained were total steps, aerobic steps, aerobic walking time, calories and distance. Steps per day were compared with international levels. Correlation statistics examined the association between physical activity and adiposity.Results: Boys in the age groups 9–11 and 12–14 years are statistically more active than girls of the same age (p = 0.005 and 0.045 respectively). Although girls’ physical activity levels tend to decrease with age, their aerobic activity levels increase with age. This group of rural children’s physical activity levels are far lower than the recommended international normative levels. No correlation was found between physical activity and adiposity.Conclusion: The pedometer data indicated that gender and age influence the activity of children. This group of rural children’s physical activity is far less than international normative levels. Nine to 11-year-old boys are the most active boys, and girls of 12–14 years old are the most aerobic active girls in this study, therefore the authors concluded that, to increase physical activity, the age group 9–11 may be the ideal age to focus on for gender-specific intervention programmes.

Doping in sport: Attitudes, beliefs and knowledge of competitive high school athletes in Gauteng Province

Objective. To determine the attitudes, beliefs and knowledge of talented young athletes residing in Gauteng regarding prohibited performance-enhancing drugs (PEDs) and anti-doping rules and regulations.Methods. This was a survey study using a quantitative research approach. South African TuksSport academy athletes at the High Performance Centre, University of Pretoria, and competitive high-school athletes at four private high schools in Gauteng completed the survey. A selfdetermined, structured questionnaire was used to establish the attitudes, beliefs and knowledge of the athletes.Results. A total of 346 (208 males, 138 females) athletes, mean (standard deviation) age 16.9 (1.4) years participated in the survey. According to this survey, 3.9% of the athletes in this survey admitted to using a prohibited PED and more than 14.0% of the athletes said they would consider using a prohibited PED if they knew they would not get caught. Ambition (46.0%) and emotional pressure (22.5%) were the primary reasons why the athletes would consider using prohibited PEDs. Even though coaches appeared to be one of the main sources of information (on PEDs and anti-doping rules), only 42.1% of the athletes felt that they were well informed.Conclusion. Controlling doping by means of testing is important. However, it may be necessary to put more emphasis on changing attitudes towards doping and implementing additional educational programmes.

A certified plasmid reference material for the standardisation of BCR-ABL1 mRNA quantification by real-time quantitative PCR

Serial quantification of BCR–ABL1 mRNA is an important therapeutic indicator in chronic myeloid leukaemia, but there is a substantial variation in results reported by different laboratories. To improve comparability, an internationally accepted plasmid certified reference material (CRM) was developed according to ISO Guide 34:2009. Fragments of BCR–ABL1 (e14a2 mRNA fusion), BCR and GUSB transcripts were amplified and cloned into pUC18 to yield plasmid pIRMM0099. Six different linearised plasmid solutions were produced with the following copy number concentrations, assigned by digital PCR, and expanded uncertainties: 1.08±0.13 × 10⁶, 1.08±0.11 × 10⁵, 1.03±0.10 × 10⁴, 1.02±0.09 × 10³, 1.04±0.10 × 10² and 10.0±1.5 copies/μl. The certification of the material for the number of specific DNA fragments per plasmid, copy number concentration of the plasmid solutions and the assessment of inter-unit heterogeneity and stability were performed according to ISO Guide 35:2006. Two suitability studies performed by 63 BCR–ABL1 testing laboratories demonstrated that this set of 6 plasmid CRMs can help to standardise a number of measured transcripts of e14a2 BCR–ABL1 and three control genes (ABL1, BCR and GUSB). The set of six plasmid CRMs is distributed worldwide by the Institute for Reference Materials and Measurements (Belgium) and its authorised distributors (https://ec.europa.eu/jrc/en/reference-materials/catalogue/; CRM code ERM-AD623a-f).

The relationship between functional movement analysis and lowerbody injury rates in adolescent female football players

Objective. To determine whether a relationship exists between the functional movement analysis (FMA) score and lower-body injury rates in high-performance adolescent female football players.Method. Observations included a baseline FMA score and medical injury reports. Data were collected from 24 players’ injury and illness records over a 38-week training period. All football injuries requiring medical attention (including stiffness, strains, contusions and sprains) and/or the removal from a session, leading to training restriction, were included in the study. Off-season weeks were excluded. Pearson’s product-moment correlation coefficient was calculated to assess the strength of the linear relationship between the FMA score and the number of medical visits, and between the number of medical visits and the number of training-restriction days.Results. There was no evidence of a relationship between the FMA score and injury risk in teenage female football players (r=0.016; p=0.940). A strong indication of a cyclical season in the training schedule was noticed over the 38-week study period. A substantive negative correlation (r=-0.911; p=0.032) was seen in the number of medical visits compared with the training-restriction days. Injuries during two peak periods could have resulted from overuse, increased training load, stress and overtraining.Conclusion. It could not be shown that a high FMA score was associated with a lower risk of injury. The ultimate goal is thus to reduce recurrent injury in players with a high FMA count. The regular medical visits observed suggest that player condition is maintained by means of reducing injury and managing training-restriction days. Our findings are in accordance with previous studies in terms of the lower limb being the most frequent region of injury, specifically the knee. This study supports previous suggestions that it is essential to develop a prevention strategy to measure trauma and recovery.

The relationship between functional movement analysis and lowerbody injury rates in adolescent female football players

Objective. To determine whether a relationship exists between the functional movement analysis (FMA) score and lower-body injury rates in high-performance adolescent female football players.Method. Observations included a baseline FMA score and medical injury reports. Data were collected from 24 players’ injury and illness records over a 38-week training period. All football injuries requiring medical attention (including stiffness, strains, contusions and sprains) and/or the removal from a session, leading to training restriction, were included in the study. Off-season weeks were excluded. Pearson’s product-moment correlation coefficient was calculated to assess the strength of the linear relationship between the FMA score and the number of medical visits, and between the number of medical visits and the number of training-restriction days.Results. There was no evidence of a relationship between the FMA score and injury risk in teenage female football players (r=0.016; p=0.940). A strong indication of a cyclical season in the training schedule was noticed over the 38-week study period. A substantive negative correlation (r=-0.911; p=0.032) was seen in the number of medical visits compared with the training-restriction days. Injuries during two peak periods could have resulted from overuse, increased training load, stress and overtraining.Conclusion. It could not be shown that a high FMA score was associated with a lower risk of injury. The ultimate goal is thus to reduce recurrent injury in players with a high FMA count. The regular medical visits observed suggest that player condition is maintained by means of reducing injury and managing training-restriction days. Our findings are in accordance with previous studies in terms of the lower limb being the most frequent region of injury, specifically the knee. This study supports previous suggestions that it is essential to develop a prevention strategy to measure trauma and recovery.

X-ray scattering measurements of strong ion-ion correlations in shock-compressed aluminum

The strong ion-ion correlation peak characteristic of warm dense matter (WDM) is observed for the first time using simultaneous angularly, temporally, and spectrally resolved x-ray scattering measurements in laser-driven shock-compressed aluminum. Laser-produced molybdenum x-ray line emission at an energy of 17.9 keV is employed to probe aluminum compressed to a density of ρ>8 g/cm(3). We observe a well pronounced peak in the static structure factor at a wave number of k=4.0 Å(-1). The measurements of the magnitude and position of this correlation peak are precise enough to test different theoretical models for the ion structure and show that only models taking the complex interaction in WDM into account agree with the data. This also demonstrates a new highly accurate diagnostic to directly measure the state of compression of warm dense matter.

HIV sero-positivity in recently admitted and long-term psychiatric in-patients: prevalence and diagnostic profile

OBJECTIVE

Research on HIV in South Africa has not reflected the impact of the disease on psychiatric patients. The aims of the study were: to compare the HIV prevalence among patient groups in Weskoppies Hospital; to compare psychiatric diagnoses of infected and non-infected patients; to assess intravenous drug use and high-risk sexual behaviour; to establish HIV-syphilis Association; and to investigate the rapid test performance for screening, compared to the confirmatory ELISA test.

METHOD

Onehundred-and-ninety-five patients were grouped into four categories according to their duration of admission and gender. HIV rapid testing, HIV ELISA, syphilis-RPR and TPHA testing were performed.

RESULTS

The HIV prevalence of 11% in the sample was significantly associated with 'gender-and-duration-of-admission' categories (p = 0.003). No significant association between HIV infection and psychiatric diagnoses or intravenous drug use was found, but a significant association existed between HIV infection and high-risk sexual behaviour (p = 0.002), and between HIV and syphilis (p = 0.012). The HIV rapid screening test had a sensitivity of 91.7% and a specificity of 98.2%.

CONCLUSION

The overall HIV prevalence at Weskoppies Hospital remains lower than the national average, but has increased since a previous local study. The rapid test for HIV had a lower sensitivity than was expected, and it is recommended that HIV ELISA testing be performed as a first line test in the setting of hospitalised patients. Due to the high prevalence of HIV and syphilis in the psychiatric population it is recommended that all patients be tested for both of these diseases.

A survey of HIV-related knowledge among adult psychiatric patients. A South African Study - Part 2

OBJECTIVE

Studies have reported an increased prevalence of HIV infection among psychiatric patients. Inaccurate HIV knowledge is included as a factor in the increased risk of HIV infection in the mentally ill, but few studies have looked specifically at this factor. The aims of the study were to determine the knowledge of HIV and its transmission among adult psychiatric patients at Weskoppies Hospital and to determine the relationship between HIV knowledge and HIV risk behaviour.

METHOD

Structured interviews were conducted with 113 consenting adult patients at Weskoppies Hospital. They were divided into three groups according to their length of hospital stay. The structured interview included questions about demographic data, the diagnoses and the AIDS Risk Behaviour Knowledge Test (AIDS-KT). Scores of 13 out of 13 represented accurate knowledge of HIV (level I); scores of 10-12 represented good knowledge (level II); scores of ≤ 9 represented poor knowledge (level III).

RESULTS

A total of 104 patients (92%) demonstrated excellent knowledge of HIV and its transmission (levels I and II). There was no significant linear association between HIV knowledge and risk-behaviour scores (Pearson's correlation coefficient r= -0.11).

CONCLUSION

The presence of high-risk behaviours despite good HIV-related knowledge in this group of patients, leads us to think that knowledge alone will not limit HIV risk behaviours. For this reason, educational programmes should not be limited to interventions that simply increase knowledge about HIV infection but should extend to clinical factors, including patients' motivation and readiness to change their behaviour.

PACS: Do clinical users benefit from it as a training adjunct?

Background. Over the past four years, Steve Biko Academic Hospital has been in the process of implementing and refining the use of a picture archiving and communications system (PACS). As part of a post-implementation refining process, it is necessary to evaluate user-perceptions in order to improve on good system qualities and correct flaws. Aim. The aim of this study was to assess whether medical clinicians perceived PACS as a positive adjunct to training and teaching opportunities – specifically those opportunities related to radiological image viewing and interpretation as part of patient case discussions. Method. Standardised questionnaires with ‘free text’ and ‘option selection’ questions were distributed to clinicians who, as part of their training, rotated at Steve Biko Academic Hospital (where a PACS is in place) as well as other teaching hospitals without a PACS. Between February 2009 and May 2009, approximately 400 questionnaires were distributed. As a result of constant academic rotations, leave schedules of medical staff and posts vacated, questionnaires could not be distributed to the entire target population that was estimated to be in the region of 550 medical clinicians (comprising senior medical students, interns, medical officers, registrars and consultants). Of the 400 questionnaires distributed, 189 completed questionnaires were returned. Completion of the questionnaires was voluntary and anonymous. Results and conclusion. Although a PACS relates specifically to the archiving and retrieval of radiological images and reports, it became clear from the feedback received from medical clinicians (who are ward-based, theatre-based or clinic-based users of a digital system) that many other factors, such as lack of adequate hardware and sub-optimal personal IT proficiency, contributed to some of the negative PACS-related perceptions and ‘lost teaching opportunities’ reported. Negative comments specifically related to PACS as a training adjunct included the frustrations associated with PACS downtime (especially during the period in 2009 when many electrical power cuts were experienced nationwide, resulting in network interruptions) and slow image retrieval during peak work-flow times. The advantages of PACS as a positive training adjunct were highlighted in the areas of multi-site viewing and consultation, the possibility of image manipulation and measurement tools, and better overall image quality. Clinicians felt that their training experience was also enhanced because of better patient follow-up made possible by access to all previous radiological imaging of a particular patient. Of the clinicians who completed the questionnaires, 63.5% felt that the PACS at Steve Biko Academic Hospital contributed positively to their training by creating more overall learning opportunities than other training environments without a PACS.

Establishment of a standardized multiplex assay with the analytical performance required for quantitative measurement of BCR-ABL1 on the international reporting scale

Accurate and standardized methods for the quantitative measurement of BCR–ABL1 are a prerequisite for monitoring of treatment response in t(9;22)-positive leukemia. Here, we describe a novel multiplex assay system based on the proven TaqMan and Armored RNA technologies and optimized for sensitive detection of three BCR–ABL1 fusion transcripts and ABL1 in a single reaction. Analytical experiments confirmed the absence of significant competition between the simultaneous amplification reactions and established the sensitivity, linearity and precision of the assay. Comparative studies with 115 clinical specimens resulted in high qualitative and quantitative agreement with independent singleplex laboratory-developed tests routinely used in clinical testing. Direct comparison with a reference laboratory calibrated to the international scale (IS) demonstrated minimal analytical bias between methods and an overall accuracy and precision within the performance range required for quantitative measurement of BCR–ABL1 on the IS. We conclude that detection of e1a2, b2a2, b3a2 and ABL1 can be achieved in a multiplex assay format compatible with IS reporting. Further clinical validation of the assay could improve the operational efficiency of clinical laboratories, increase their adherence to current recommendations for b2a2/b3a2 reporting on the IS and provide for the first time an opportunity to standardize e1a2-monitoring results.

Vitamin C supplementation in very preterm infants: a randomised controlled trial

OBJECTIVE

To determine whether regulating vitamin C (ascorbic acid: AA) intake to achieve higher or lower plasma concentrations was associated with improved clinical outcome.

DESIGN

A double blind, randomised controlled trial.

SETTING

Neonatal intensive care unit at Christchurch Women's Hospital.

PATIENTS

Infants with birth weight <1500 g or gestation <32 weeks, admitted to the unit within 48 hours of birth.

INTERVENTION

Infants were randomised to one of three protocols with regard to AA supplementation for the first 28 days of life: group LL received low supplementation throughout; group LH received low until day 10 and then high: group HH received high throughout.

MAIN OUTCOME MEASURES

Primary outcome measures were oxygen requirement at 28 days and 36 weeks postmenstrual age, total days supplemental oxygen, and retinopathy of prematurity. AA concentrations were measured at study entry (day 2), and days 10, 21, and 28.

RESULTS

A total of 119 infants were enrolled over 24 months (mean gestation 28.4 weeks; birth weight 1161 g). Six infants died, and these had significantly higher AA concentrations before randomisation than surviving infants (116 micromol/l (95% confidence interval 90 to 142) v 51 micromol/l (45 to 58), p<0.0001). There were no significant differences in primary outcomes between the groups. However, the proportion of surviving infants with an oxygen requirement at 36 weeks postmenstrual age in group HH (19%) was half that in group LL (41%) (p=0.06).

CONCLUSIONS

In a randomised controlled trial, no significant benefits or harmful effects were associated with treatment allocation to higher or lower AA supplementation throughout the first 28 days of life.

Die-off of enteric bacterial pathogens during mesophilic anaerobic digestion

Conventionally treated sewage sludge may contain high concentrations of potentially pathogenic microorganisms and additional treatment is required to minimise the risks to health if it is to be recycled to agricultural land. Mesophilic anaerobic digestion (MAD) is the most widely used process in the UK for stabilising sludge prior to agricultural recycling, but little is known about the fate of a number of enteric pathogens as the sludge passes through the treatment processes. The aim of this study was to determine the efficiency of MAD in removing the bacterial enteric pathogens, Salmonella senftenberg, Listeria monocytogenes and Campylobacter jejuni which were added as a spike to the digester feedstock, together with the die-off of indigenous Escherichia coli already present in the sludge. The primary sludge digestion stage of MAD was found to achieve a log removal of 1.66 for E. coli, 2.23 for L. monocytogenes and 2.23 for S. senftenberg. However, the extent of die-off was a function of the numbers of pathogens in the feed and as these increased the log removal also increased. The numbers of C. jejuni were not affected by primary sludge digestion. Additional die-off was provided by secondary sludge digestion with log removals of 1.70 for E. coli, 2.10 for S. senftenberg and 0.36 for C. jejuni.