An audit of apixaban prescribing for atrial fibrillation in a hospital setting

The oral anticoagulant apixaban is becoming a popular first-line option for prevention of stroke and systemic embolism, in adults with non-valvular atrial fibrillation (NVAF) exhibiting one or more risk factors. Two dosage regimens are recommended: 5mg twice daily or 2.5mg twice daily; the latter is deemed appropriate if creatinine clearance (CrCl) 15-29 ml/min or at least two of age ≥ 80 years, body weight ≤ 60 kg, or serum creatinine ≥ 133 micromol/L are satisfied. These criteria derive from results of two large successful clinical trials1,2 and have formed the basis of local prescribing guidelines. This audit has shown that current evidence-based guidelines are not being fully adhered to, especially when prescribing for elderly patients. Consequently, these patients are potentially put at risk of subtherapeutic dosing, in turn increasing their probability of stroke. Current published evidence does not justify reducing doses based solely on age, despite anecdotal concerns of local prescribers of an increased risk of haemorrhage. Prescribers should remain vigilant and document any reasons for dosing the product outside of its licence

Tertiary Dentine Frequencies in Extant Great Apes and Fossil Hominins

Tertiary dentine forms when an odontoblast is directly affected by stimuli, commonly through occlusal wear and caries. In this study the presence of tertiary dentine was recorded in three South African fossil hominin species ('Australopithecus africanus, Homo naledi and Paranthropus robustus'), and two extant great ape species ('Gorilla gorilla gorilla' and 'Pan troglodytes'). Frequencies of tertiary dentine were calculated for each species based on macroscopic observations of teeth with dentine exposed through occlusal wear. Overall, the three hominin species have similar tertiary dentine frequencies ranging from 12% to 16.13%. In contrast, over 90% of permanent gorilla teeth with dentine visible show tertiary dentine. Chimpanzees fall between these extremes, with 47.21% of permanent teeth affected. Deciduous teeth follow the same pattern. Species variances are not related to differences in occlusal wear. Instead, some species appear predisposed to produce tertiary dentine earlier/faster, or more often, than other species. Therefore, tertiary dentine formation has the potential to provide useful information on fossil specimens. For example, the uniformly low frequency of tertiary dentine formation in hominins may relate to diet, or be due to thick enamel having a similar role in preventing loss of function of teeth, i.e., extending the life of a tooth. In contrast, tertiary dentine is clearly an important mechanism for normal dental function in gorillas, and may have evolved to help maintain shearing function

Correction: Threatened Caribbean Coral Is Able to Mitigate the Adverse Effects of Ocean Acidification on Calcification by Increasing Feeding Rate.

Global climate change threatens coral growth and reef ecosystem health via ocean warming and ocean acidification (OA). Whereas the negative impacts of these stressors are increasingly well-documented, studies identifying pathways to resilience are still poorly understood. Heterotrophy has been shown to help corals experiencing decreases in growth due to either thermal or OA stress; however, the mechanism by which it mitigates these decreases remains unclear. This study tested the ability of coral heterotrophy to mitigate reductions in growth due to climate change stress in the critically endangered Caribbean coral Acropora cervicornis via changes in feeding rate and lipid content. Corals were either fed or unfed and exposed to elevated temperature (30°C), enriched pCO2 (800 ppm), or both (30°C/800 ppm) as compared to a control (26°C/390 ppm) for 8 weeks. Feeding rate and lipid content both increased in corals experiencing OA vs. present-day conditions, and were significantly correlated. Fed corals were able to maintain ambient growth rates at both elevated temperature and elevated CO2, while unfed corals experienced significant decreases in growth with respect to fed conspecifics. Our results show for the first time that a threatened coral species can buffer OA-reduced calcification by increasing feeding rates and lipid content

Of teeth and algorithms: machine learning reveals the taxonomy of Sima de los Huesos

The taxonomic attribution of the skeletal material of Sima de los Huesos (SH, Spain) has puzzled researchersfor decades. At the time of their discovery, the SH hominins were considered as pre-Neanderthal based on their morphology [1]. Later, tooth dimensions were found to link the SH sample to middle Pleistocene specimens such as Mauer, Montmaurin, and Arago II [2], which are commonly ascribed to Homo heidelbergensis. More recently, a close relationship between Neanderthals and the SH specimens was suggested based on the morphology of cranial vault and face, in particular regarding the masticatory apparatus [3]. Decades of unresolved debate produced three plausible scenarios for the status of SH in the human ancestry: (I) SH has to be regarded as part of the variability of H. heidelbergensis, (II) SH should be considered H. neanderthalensis, (III) SH andH. heidelbergensiscould represent two separate evolutionary lineages co-existing during middle Pleistocene in Eurasia, with SH being phylogenetically closer to Neanderthals. In this work, we applied supervised machine learning to test for the affinity of SH (N: 126) to H. heidelbergensis (N: 13), H. neanderthalensis (N: 73), and H. sapiens (N: 403). The sample included Mesio-Distal and Bucco-Lingual diameters of mandibular postcanine dentition. Because of the fragmentary nature of the dental fossil and archaeological records, several missing data were included in the dataset and were estimated using Multiple Imputation via Predictive Mean Matching [4]. To avoid biases due to disproportions in sample size, missing data were estimated separately for each group considered. A recursive partitioning algorithm known as Conditional Inference Tree (CIT) [5] was used to build a hierarchical model for predicting the classification of dental metric data into each of the categorical groups considered (SH, H. heidelbergensis, H. neanderthalensis, and H. sapiens). The data was divided in one training set and one test set. The training set (N: 105) was used to allow the CIT algorithm to determine the best classification solution for the dental data. The test set (N: 497) was necessary to control the accuracy of classification. Our results show that when SH is considered as part of H. heidelbergensis it is easily misclassified as Neanderthal (33.6% accuracy). On the other side, SH is recognised as an independent group when other H. heidelbergensis specimens are discarded from the analysis (95.6% accuracy). In both cases, the classification is based on a major contribution of the Bucco-Lingual diameter of the third premolar in association with the dimensions of the second and third molars. The accuracy associated with the H. sapiens and H. neanderthalensis samples indicates that the model is capable of classifying discrete taxonomic groups. Our results support the hypothesis that SH represents a distinct evolutionary lineage from H. heidelbergensis and suggest that SH could be closely related to “classic” Neanderthals. This work represents the first application of supervised machine learning to Palaeoanthropology and highlights the potential of this field to the study of human evolution. References:[1] Aguirre, E., & De Lumley, M. A. (1977). Fossil men from Atapuerca, Spain: their bearing on human evolution in the Middle Pleistocene. Journal of human evolution, 6(8), 681-688.[2] de Castro, J. M. B. (1986). Dental remains from Atapuerca (Spain) I. Metrics. Journal of Human Evolution, 15(4), 265-287.[3] Arsuaga, J. L., Martínez, I., Arnold, L. J., Aranburu, A., Gracia-Téllez, A., Sharp, W. D., ... & Poza-Rey, E. (2014). Neandertal roots: Cranial and chronological evidence from Sima de los Huesos. Science, 344(6190), 1358-1363.[4] Morris, T. P., White, I. R., & Royston, P. (2014). Tuning multiple imputation by predictive mean matching and local residual draws. BMC medical research methodology, 14(1), 75.[5] Strobl, C., Malley, J., & Tutz, G. (2009). An introduction to recursive partitioning: rationale, application, and characteristics of classification and regression trees, bagging, and random forests. Psychological methods, 14(4), 32

High frequency of dental caries and calculus in dentitions from a British medieval town

Objective: Dental pathology and tooth wear data can offer valuable insights into the diet and behaviou r of past populations. This study aimed to investigate the presence of dieta r y continuity by examining different types of dental pathology and tooth wear in a medieval sample from the United Kingdom, comparing them to earlier and later samples from the same location. Design: A comprehensive examination was conducted on 41 individuals (comprising 914 permanent teeth) retrieved from the medieval cemeter y of St. Owens Church in Southgate Street, Gloucester, UK . The research focused on documenting and analysing various types of dental patholog y and tooth wear, such as dental caries, calculus, and tooth chipping. The frequency of these specific pathologies and wear patterns was then compared to existing literature. Additionally, non-masticator y tooth wear was also evaluated as part of the study. Results: The sample exhibits high levels of carious lesions and calculus (24 % and 74 % of teeth respectively). Anterior teeth also show an elevated chipping frequency, and along with occlusal notches on the maxilla r y central incisors suggest teeth were regularly used for non-masticator y purposes. Conclusions: Caries frequency is similar to sites from later periods and may relate to the early adoption of consuming refined carbohydrates. However, remains from the same area, but the earlier Roman period, also show s high rates of caries and calculus, suggesting a continuation of consuming certain cariogenic foods, or certain behavioural/environmental factors, may instead be responsible for these patholog y and wear patterns

Views of medical and non-medical prescribers on the prescribing of benzodiazepines to drug misusers within NHS Lanarkshire

The article examines the views of medical and non-medical prescribers within the Addiction Service Community Prescribing Service in NHS Lanarkshire on the prescribing of benzodiazepines to drug misusers in primary care. Both a focus group and a semi-structured questionnaire were utilised to gather the data from the practitioners, with a response rate of 93.8% to the questionnaire. The results were statistically analysed and although determined to be statistically insignificant, respondents demonstrated a positive correlation (p > 0.05) with respect to the initiation of local guidelines when prescribing benzodiazepines to drug misusers. The article demonstrates that, despite benzodiazepine use being highly prevalent among drug users in Scotland, a combination of positive attitudes to prescribing from practitioners and the implementation of local guidelines within NHS Lanarkshire Addictions Services have contributed to a reduction in prescribing benzodiazepine. The article highlights the need for training and support for prescribers which, along with increased compliance with local guidelines, could further enhance the positive attitudes of the prescribers and ultimately further reduce prescribing benzodiazepines