Evidence of wet-dry cycles and mega-droughts in the Eemian climate of southeast Australia.

Understanding past climate variability is critical to informing debate of likely impacts of global warming on weather and climate, and water resources. Here we present a near annual resolution reconstruction of climate developed from a speleothem that spans the Eemian [Marine Isotope Stage 5e (MIS 5e)] from 117,500 to 123,500 years BP-the most recent period in the Earth's history when temperatures were similar to those of today. Using 25 Mg, 88Sr, and 137Ba as proxies, we show the first indication of solar and teleconnection cyclic forcing of Eemian climate in southeast Australia, a region at present often affected by severe drought and bushfires. We find evidence for multi-centennial dry periods interpreted as mega-droughts, and highlight the importance of understanding the causes of these in the context of a rapidly warming world, where temperatures are now, or projected to exceed those of the Eemian.

Serum Magnesium Measurements After Parathyroidectomy for Primary Hyperparathyroidism: Should It be Routine?

BACKGROUND: Parathyroidectomy is the treatment of choice in primary hyperparathyroidism (PHPT). Following surgery, significant changes in bone and mineral metabolism may follow, but routine magnesium monitoring is not standard practice. The occurrence of significant clinical events linked to hypomagnesaemia in 3 patients after parathyroidectomy led to our evaluation of magnesium levels after surgery for PHPT. METHODS: Serum magnesium levels before and after parathyroidectomy for PHPT were prospectively evaluated in a single centre over a year. The incidence and severity of hypomagnesaemia and its correlation with other biochemical variables were assessed. RESULTS: A total of 138 patients underwent parathyroidectomy for PHPT. Pre-operative and day 1 post-operative serum magnesium levels were available in 57/138 (41.3%) and 99/138 (71.7%) patients, respectively. Serum magnesium decreased significantly after surgery (mean ± SD of 0.85 ± 0.08 and 0.75 ± 0.11 mmol/L, respectively, p < 0.001). On the day after parathyroidectomy, 31/99 (31.3%) patients had hypomagnesaemia (<0.70 mmol/L); in 3 of whom it was severe (<0.50 mmol/L). Patients with hypomagnesaemia had lower pre-operative magnesium (mean ± SD of 0.78 ± 0.06 and 0.87 ± 0.07 mmol/L, p < 0.001), higher pre-operative calcium [median (IQR) of 2.83 (2.71-2.99) and 2.71 (2.63-2.80) mmol/L, p = 0.001] and higher post-operative calcium [median (IQR) of 2.41 (2.30-2.51) and 2.35 (2.28-2.43) mmol/L, p = 0.046] compared to those with normomagnesaemia. In addition, these patients demonstrated higher drop in calcium levels after surgery (0.44 ± 0.20 and 0.35 ± 0.18 mmol/L, p = 0.033). Magnesium levels after surgery correlated positively with pre-operative magnesium (r = 0.561, p < 0.001) and post-operative PTH (r = 0.210, p = 0.037) and negatively with pre-operative adjusted calcium (r = - 0.389, p < 0.001). CONCLUSIONS: Serum magnesium decreased significantly following parathyroidectomy for PHPT and nearly a third of patients developed post-operative, mostly mild hypomagnesaemia. Whilst routine serum magnesium measurements could facilitate prompt recognition and treatment of this electrolyte disturbance, further research needs to establish the clinical importance of mild hypomagnesaemia in these clinical settings and, if indicated, to devise optimal treatment strategies.

The National Undergraduate Neuroanatomy Competition: Five years of educating, inspiring and motivating our future neurologists and neurosurgeons

Neurological conditions are common so a knowledge of neuroanatomy is necessary for junior doctors. Additionally, some students have a particular interest in neuroscience. However, little time is dedicated to neuroanatomy in the medical curriculum, and many students struggle with neuroanatomy. The National Undergraduate Neuroanatomy Competition (NUNC) aims to support the development of neuroanatomical knowledge among medical students and promote interest in neurosciences. Students who attended the NUNC completed a series of neuroanatomy-based examinations and a questionnaire investigating aspects of neuroanatomy teaching and resources at their home university. 387 students attended the NUNC between 2013 and 2017, of which 382 had a complete data set (response rate 98.7%). Male students significantly outperformed female students (p<0.0001) and clinical students outperformed pre-clinical students (p<0.05). Best answered questions were on the spine (average score 53.9%), and the most poorly answered questions were on the vasculature (average score 44.7%). Students felt that the neuroanatomy teaching, time spent on neuroanatomy and dissection/prosection resources were all reasonable (6-7/10) at their home institution. Elearning resources were rated more poorly (5.4/10). We conclude that the NUNC gives students the opportunity to enhance their neuroanatomical knowledge and gives keen students the chance to develop their interest

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A systematic review of trends in the selective exclusion of older participant from randomised clinical trials.

INTRODUCTION: The unjustified exclusion of older participants from clinical trials creates research populations that are non-representative, in turn creating difficulties applying research to the target populations. The aim of this study was to assess the proportion of randomised control trials (RCTs) that have unexplained upper age limits and review whether this proportion is reducing over time. METHODS: All RCTs in BMJ, Lancet, JAMA and NEJM from 1998 to 2015 were reviewed to identify any specified upper-age cut off and, if so, whether this exclusion criterion had an explanation in the text. The proportion of RCTs with an unexplained cut off was then correlated over time to look for any changes. RESULTS: 5680 papers were identified and 1339 excluded as they did not meet the search criteria. Of the remaining 4341 RCTs, 1258 (29%) had upper age limits specified, 1168 (92.8%) of which did not have any explanation for this cut off, a total of 26.9% of the RCTs reviewed. Over the 18-year period there was limited but statistically significant decrease in the proportion of RCTs with unexplained upper age limits (Pearson Correlation -0.609, P valve 0.007). CONCLUSION: Despite being the highest consumers of medical interventions and medications, this review highlights that older patients remain under-represented in clinical trial with only modest improvements despite increasing awareness of the problem. Future research must continue to adapt to provide insight into the differential effects of medical treatments in older patients by ensuring that trial participants are representative of the patient population receiving the intended therapy.

Can medical students accurately predict their learning? A study comparing perceived and actual performance in neuroanatomy.

It is important that clinicians are able to adequately assess their level of knowledge and competence in order to be safe practitioners of medicine. The medical literature contains numerous examples of poor self-assessment accuracy amongst medical students over a range of subjects however this ability in neuroanatomy has yet to be observed. Second year medical students attending neuroanatomy revision sessions at the University of Southampton and the competitors of the National Undergraduate Neuroanatomy Competition were asked to rate their level of knowledge in neuroanatomy. The responses from the former group were compared to performance on a ten item multiple choice question examination and the latter group were compared to their performance within the competition. In both cohorts, self-assessments of perceived level of knowledge correlated weakly to their performance in their respective objective knowledge assessments (r = 0.30 and r = 0.44). Within the NUNC, this correlation improved when students were instead asked to rate their performance on a specific examination within the competition (spotter, rS = 0.68; MCQ, rS = 0.58). Despite its inherent difficulty, medical student self-assessment accuracy in neuroanatomy is comparable to other subjects within the medical curriculum. Anat Sci Educ 9: 488-495. © 2016 American Association of Anatomists.

Decreasing troponin turnaround time in the emergency department using the central laboratory: A process improvement study.

OBJECTIVES: To implement collaborative process improvement measures to reduce emergency department (ED) troponin turnaround time (TAT) to less than 60min using central laboratory. DESIGN AND METHODS: This was an observational, retrospective data study. A multidisciplinary team from the ED and laboratory identified opportunities and developed a new workflow model. Process changes were implemented in ED patient triage, staffing, lab collection and processing. Data collected included TAT of door-to-order, order-to-collect, collect-to-received, received-to-result, door-to-result, ED length of stay, and hemolysis rate before (January-August, 2011) and after (September 2011-June 2013) process improvement. RESULTS: After process improvement and implementation of the new workflow model, decreased median TAT (in min) was seen in door-to-order (54 [IQR43] vs. 11 [IQR20]), order-to-collect (15 [IQR 23] vs. 10 [IQR12]), collect-to-received (6 [IQR8] vs. 5 [IQR5]), received-to-result (30 [IQR12] vs. 24 [IQR11]), and overall door-to-result (117 [IQR60] vs. 60 [IQR40]). A troponin TAT of <60min was realized beginning in May 2012 (59 [IQR39]). Hemolysis rates decreased (14.63±0.74 vs. 3.36±1.99, p<0.0001), as did ED length of stay (5.87±2.73h vs. 5.15±2.34h, p<0.0001). Conclusion Troponin TAT of <60min using a central laboratory was achieved with collaboration between the ED and the laboratory; additional findings include a decreased ED length of stay.

Assessment and management of older people with sarcopenia.

Sarcopenia, the loss of skeletal muscle mass and function with age, is common in older people. It is associated with increased morbidity and mortality, and a greater risk of admission to hospital and care homes. This article identifies the risk factors and consequences of sarcopenia, and describes how nurses and GPs can recognise patients at particular risk of developing the condition. Evidence for the management of sarcopenia is discussed with regard to lifestyle and potential future therapeutic developments.