Bonobo and chimpanzee gestures overlap extensively in meaning.

Cross-species comparison of great ape gesturing has so far been limited to the physical form of gestures in the repertoire, without questioning whether gestures share the same meanings. Researchers have recently catalogued the meanings of chimpanzee gestures, but little is known about the gesture meanings of our other closest living relative, the bonobo. The bonobo gestural repertoire overlaps by approximately 90% with that of the chimpanzee, but such overlap might not extend to meanings. Here, we first determine the meanings of bonobo gestures by analysing the outcomes of gesturing that apparently satisfy the signaller. Around half of bonobo gestures have a single meaning, while half are more ambiguous. Moreover, all but 1 gesture type have distinct meanings, achieving a different distribution of intended meanings to the average distribution for all gesture types. We then employ a randomisation procedure in a novel way to test the likelihood that the observed between-species overlap in the assignment of meanings to gestures would arise by chance under a set of different constraints. We compare a matrix of the meanings of bonobo gestures with a matrix for those of chimpanzees against 10,000 randomised iterations of matrices constrained to the original data at 4 different levels. We find that the similarity between the 2 species is much greater than would be expected by chance. Bonobos and chimpanzees share not only the physical form of the gestures but also many gesture meanings.

Sperm Storage in a Family-Living Lizard, the Tree Skink (Egernia striolata).

The ability to produce viable offspring without recently mating, either through sperm storage or parthenogenesis, can provide fitness advantages under a suite of challenging ecological scenarios. Using genetic analysis, we demonstrate that 3 wild-caught female Tree Skinks (Egernia striolata) reproduced in captivity with no access to males for over a year, and that this is best explained by sperm storage. To the best of our knowledge, this is the first time female sperm storage has been documented in any monogamous family-living reptile, including social Australian egerniine skinks (from the subfamily Egerniinae). Furthermore, by using paternal reconstruction of genotypes we show that captive-born offspring produced by the same females in the preceding year, presumably without sperm storage, were sired by different males. We qualitatively compared aspects of these females' mates and offspring between years. The parents of each litter were unrelated, but paternal and offspring genotypes from litters resulting from stored sperm were more heterozygous than those inferred to be from recent matings. Family-living egerniine skinks generally have low rates of multiple paternity, yet our study suggests that female sperm storage, potentially from outside social partners, offers the real possibility of benefits. Possible benefits include increasing genetic compatibility of mates and avoiding inbreeding depression via cryptic female choice. Sperm storage in Tree Skinks, a family-living lizard with a monogamous mating system, suggests that females may bet-hedge through extra-pair copulation with more heterozygous males, reinforcing the idea that females could have more control on reproductive outcomes than previously thought.

Incidence and significance of injuries on secondary CT imaging after initial selective imaging in blunt trauma patients.

OBJECTIVE: It is unclear if additional computerized tomography (CT) imaging is warranted after injuries are identified on CT in blunt trauma patients. The objective of this study was to determine the incidence and significance of injuries identified on secondary CT imaging after identification of injuries on initial CTs in blunt trauma patients. METHODS: This was a retrospective cohort study at an academic Level 1 trauma center with a two-tiered trauma system. INCLUSION CRITERIA: age ≥ 18, level 2 trauma activation, injury identified on initial CT, and secondary CTs ordered. Secondary injuries were categorized as resulting in: no changes, minor changes, or major changes in management. RESULTS: 537 patients underwent 1179 initial CT scans which identified 744 injuries. There were 1094 secondary CTs which identified 143 additional injuries in 94 (18%) patients. 9 (1.7%) patients had at least one major management change and 64 (12%) had at least one minor management change. Rib fracture(s) was the most common injury on secondary scans [45/143 (32%)]. The major management changes were: tube thoracostomy for pneumothorax (4 patients), blood transfusion for hemoperitoneum (1 patient), surgery for acetabular fracture (1 patient), thoracolumbar brace for spine fracture (2 patients) and angiography for splenic injury (1 patient). CONCLUSION: While a significant proportion of patients (18%) had injuries on secondary CT, only 1.7% of patients had a resultant major management change. Future research is warranted to determine the need for additional CT imaging after an initial selective imaging strategy in blunt trauma patients.

Trends in United States neurosurgery residency education and training over the last decade (2009-2019).

OBJECTIVE: Postgraduate training in medicine has been under scrutiny in the last 10 years, with a focus on improving residents' education. The aim of this study was to quantify trends in neurosurgery residency (NSR) training and education over the last 10 years. METHODS: The authors assessed Accreditation Council for Graduate Medical Education (ACGME), National Resident Matching Program, and American Board of Neurological Surgeons records and searched PubMed to collate 2009-2019 data. Analyzed trends included residents' demographic data, programs' characteristics, graduation and attrition rates, match data, resident case logs, and qualitative educational curriculum changes. RESULTS: Significant increases in residents' demographic data (p < 0.05) included the number of female residents (from 12.7% to 17.6%) and the absolute number of residents (from 1112 to 1462). Age (mean 28.8 years), ethnicity, and number of residents per program (mean 13 residents per program) were unchanged. There were 16 new ACGME NSR programs, with currently 115 programs nationwide. The number of applicants per year (324 applicants per year) and the matching rate (mean 64%) remained stable. The mean attrition rate of 2.6% (range 2%-4%) was higher than the mean 2.1% ACGME attrition rate, a rate that decreased from 3% in 2009 to 1.6% in 2019. Education curriculum changes aimed at the standardization of training across the US included residents' boot camp (2009), the Milestones project (2012), and mandatory 7-year training initiated in 2013. An increase in endovascular, functional, trauma, and spine resident caseload was noted. The number of yearly publications about US NSR education has significantly increased (p < 0.05). CONCLUSIONS: NSR education has received greater attention over the last decade in the US. Standardization of training has been implemented. A steady number of students remain interested in neurosurgery, with an increased number of women entering the field. Attention to wellness, in addition to high-quality education, should be further assessed as a factor to improve the overall NSR training and retention rate.

Prior smoking and nasoseptal flap usage adversely impact quality of life and healing after endoscopic pituitary surgery.

OBJECTIVE: Endoscopic pituitary surgery (EPS) via the endonasal transsphenoidal approach is well established as an effective treatment modality for sellar masses. The objective of this study was to determine the relationship between key patient and operative variables and rhinological outcomes as determined by the 22-item Sino-Nasal Outcome Test (SNOT-22) and endoscopic scores following EPS. METHODS: Prospectively collected SNOT-22 scores and objective endoscopic data were analyzed from a cohort of 109 patients who underwent EPS and had at least 90 days of postoperative follow-up. Trends in postoperative SNOT-22 scores were analyzed using linear mixed-effects models. Time to return to baseline endoscopic score was analyzed using Cox regression. RESULTS: After adjusting for age and sex, the authors found that prior smokers had higher total and rhinological subdomain SNOT-22 scores (p < 0.01, 95% CI 5.82-16.39; p = 0.01, 95% CI 1.38-5.09, respectively) following EPS. Nasoseptal flap use also showed higher total and rhinological subdomain SNOT-22 scores (p = 0.01, 95% CI 1.62-12.60; p = 0.02, 95% CI 0.42-4.30, respectively). Prior sinonasal surgery and concurrent septoplasty did not affect the change in SNOT-22 total scores over time (p = 0.08, 95% CI -0.40 to 0.02; p = 0.33, 95% CI -0.09 to 0.29). CONCLUSIONS: The findings suggest that the evolution of healing and patient-reported quality of life (QOL) measures are multifaceted with contributions from two key variables. Nasoseptal flap usage and prior smoking status may adversely impact postoperative QOL. No variables were found to be associated with objective postoperative endoscopic findings.

Assessment of post-operative healing following endoscopic, transnasal, transsphenoidal pituitary surgery without formal sellar grafting.

INTRODUCTION: Multiple options exist for sellar reconstruction after endoscopic transnasal, transsphenoidal surgery (TSS) including free mucosa, fat, bone and synthetic materials. The objective of this study was to assess healing and mucosalization of the sellar face following TSS without formal sellar grafting or reconstruction. METHODS: Single institution retrospective chart review was conducted for patients undergoing TSS without intraoperative CSF leaks between January 2014 and March 2017 at Rush University Medical Center. No formal sellar reconstruction was performed for the entire patient group. Follow-up endoscopic data and clinical notes were coded for time to mucosalization of the sella as well as degree of abnormal mucosal healing, epistaxis, crusting and scarring. RESULTS: 83 patients were included in this study. Mean time to mucosalization was 119 days (range, 17 to 402 days). Incidence of abnormal mucosal healing, epistaxis, crusting and scarring increased from the first to the second postoperative visit but trended down by the third visit. Nasal crusting was the most common finding, followed by abnormal mucosal healing. Chi square analysis showed smoking to be associated with prolonged time to full mucosalization of the sella. Two patients (2.4%) had post-operative CSF leaks requiring lumbar drain placement. CONCLUSION: Adequate sellar healing is achievable in all cases without formal grafting or reconstruction after TSS. Great care must be exercised given the small inherent risk of unmasking a subclinical intraoperative CSF leak. Patients should be followed closely endoscopically during the first four months after TSS to minimize the impact of crusting.

Vesicular PtdIns(3,4,5)P3 and Rab7 are key effectors of sea urchin zygote nuclear membrane fusion.

Regulation of nuclear envelope dynamics is an important example of the universal phenomena of membrane fusion. The signalling molecules involved in nuclear membrane fusion might also be conserved during the formation of both pronuclear and zygote nuclear envelopes in the fertilised egg. Here, we determine that class-I phosphoinositide 3-kinases (PI3Ks) are needed for in vitro nuclear envelope formation. We show that, in vivo, PtdIns(3,4,5)P3 is transiently located in vesicles around the male pronucleus at the time of nuclear envelope formation, and around male and female pronuclei before membrane fusion. We illustrate that class-I PI3K activity is also necessary for fusion of the female and male pronuclear membranes. We demonstrate, using coincidence amplified Förster resonance energy transfer (FRET) monitored using fluorescence lifetime imaging microscopy (FLIM), a protein-lipid interaction of Rab7 GTPase and PtdIns(3,4,5)P3 that occurs during pronuclear membrane fusion to create the zygote nuclear envelope. We present a working model, which includes several molecular steps in the pathways controlling fusion of nuclear envelope membranes.

Age is but a number when considering epilepsy surgery in older adults.

BACKGROUND: A quarter of patients with newly diagnosed epilepsy are older, yet they are less likely to be offered resective surgery potentially because of clinical bias that they incur increased surgical risks. There are few peer-reviewed case series that address this cohort and their outcomes. OBJECTIVE: In the context of current literature, the objective of this study was to report on all epilepsy surgeries in patients aged 50 years or older from a tertiary care center over 15 years with an average follow-up period of 6 years. METHODS: Patients with epilepsy who underwent surgery between 2001 and 2016 were reviewed retrospectively. Inclusion criteria were age > 50 at surgery, availability of presurgical evaluation data, and minimum one year of follow-up data. We identified 34 patients. Seizure outcome was evaluated using the Engel classification system. RESULTS: Thirty-four patients aged 50 years and older out of 276 underwent epilepsy surgery. Average age at time of surgery was 55 years, and average duration of epilepsy was 30 years. Average length of follow-up was 6 years (1-15 years). Twenty-two out of 34 patients (64%) were seizure-free (Engel class I) at their last follow-up visit. Patients with lesional pathology on neuroimaging were more likely to achieve seizure freedom (p < 0.02). Parameters associated with poorer outcome included extratemporal epileptogenic focus (p = 0.07) and bitemporal interictal epileptiform activity (p = 0.003). CONCLUSION: Our study cohort is one of the largest and most representative outcome studies of this age group, following the cohort for 6 years. Our findings demonstrated that when considering epilepsy surgery in an older adult, their age should not play a determining role in the decision-a finding that is more common in modern literature.

Pediatric Brainstem Gliomas: A Retrospective Study of 180 Patients from the SEER Database.

BACKGROUND/AIMS: Large population-based studies are needed to assess the epidemiology and survival risk factors associated with pediatric brainstem gliomas. This retrospective study explores factors that may influence survival in this population. METHODS: Utilizing the SEER database, the authors retrospectively assessed survival in histologically confirmed brainstem gliomas in patients aged 17 and younger. Survival was described with Kaplan-Meyer curves and multivariate regression analysis. RESULTS: This analysis of 180 cases showed that age (hazard ratio [HR] 1.04, 95% CI 0.96-1.14, p = 0.34), non-white race (HR 1.00, 95% CI 0.35-2.85 p > 0.99), distant or invasive extension of the tumor (HR 0.4, 95% CI 0.08-2.53, p = 0.37), and radiation therapy (HR 1.27, 95% CI 0.52-3.11, p = 0.61) were not associated with decreased survival. High-grade tumor status (HR 8.64, 95% CI 3.49-21.41, p < 0.001) was associated with decreased survival. Partial resection (HR 0.11, 95% CI 0.04-0.30, p < 0.001) and gross-total resection (HR 0.03, 95% CI 0.01-0.14, p < 0.001) were associated with improved survival. CONCLUSIONS: High-grade brainstem gliomas have a worse prognosis. Early diagnosis and surgery appear to be associated with improved survival, while the role of radiation is unclear.

Acute depletion of diacylglycerol from the cis-Golgi affects localized nuclear envelope morphology during mitosis.

Dysregulation of nuclear envelope (NE) assembly results in various cancers; for example, renal and some lung carcinomas ensue due to NE malformation. The NE is a dynamic membrane compartment and its completion during mitosis is a highly regulated process, but the detailed mechanism still remains incompletely understood. Previous studies have found that isolated diacylglycerol (DAG)-containing vesicles are essential for completing the fusion of the NE in nonsomatic cells. We investigated the impact of DAG depletion from the cis-Golgi in mammalian cells on NE reassembly. Using advanced electron microscopy, we observed an enriched DAG population of vesicles at the vicinity of the NE gaps of telophase mammalian cells. We applied a mini singlet oxygen generator-C1-domain tag that localized DAG-enriched vesicles at the perinuclear region, which suggested the existence of NE fusogenic vesicles. We quantified the impact of Golgi-DAG depletion by measuring the in situ NE rim curvature of the reforming NE. The rim curvature in these cells was significantly reduced compared with controls, which indicated a localized defect in NE morphology. Our novel results demonstrate the significance of the role of DAG from the cis-Golgi for the regulation of NE assembly.

Store depletion-induced h-channel plasticity rescues a channelopathy linked to Alzheimer's disease.

Voltage-gated ion channels are critical for neuronal integration. Some of these channels, however, are misregulated in several neurological disorders, causing both gain- and loss-of-function channelopathies in neurons. Using several transgenic mouse models of Alzheimer's disease (AD), we find that sub-threshold voltage signals strongly influenced by hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels progressively deteriorate over chronological aging in hippocampal CA1 pyramidal neurons. The degraded signaling via HCN channels in the transgenic mice is accompanied by an age-related global loss of their non-uniform dendritic expression. Both the aberrant signaling via HCN channels and their mislocalization could be restored using a variety of pharmacological agents that target the endoplasmic reticulum (ER). Our rescue of the HCN channelopathy helps provide molecular details into the favorable outcomes of ER-targeting drugs on the pathogenesis and synaptic/cognitive deficits in AD mouse models, and implies that they might have beneficial effects on neurological disorders linked to HCN channelopathies.

Sensory laterality in affiliative interactions in domestic horses and ponies (Equus caballus).

Many studies have been carried out into both motor and sensory laterality of horses in agonistic and stressful situations. Here we examine sensory laterality in affiliative interactions within four groups of domestic horses and ponies (N = 31), living in stable social groups, housed at a single complex close to Vienna, Austria, and demonstrate for the first time a significant population preference for the left side in affiliative approaches and interactions. No effects were observed for gender, rank, sociability, phenotype, group, or age. Our results suggest that right hemisphere specialization in horses is not limited to the processing of stressful or agonistic situations, but rather appears to be the norm for processing in all social interactions, as has been demonstrated in other species including chicks and a range of vertebrates. In domestic horses, hemispheric specialization for sensory input appears not to be based on a designation of positive versus negative, but more on the perceived need to respond quickly and appropriately in any given situation.

Endomembrane PtdIns(3,4,5)P3 activates the PI3K-Akt pathway.

PKB/Akt activation is a common step in tumour growth, proliferation and survival. Akt activation is understood to occur at the plasma membrane of cells in response to growth factor stimulation and local production of the phosphoinositide lipid phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5)P3] following phosphoinositide 3-kinase (PI3K) activation. The metabolism and turnover of phosphoinositides is complex--they act as signalling molecules as well as structural components of biological membranes. The localisation and significance of internal pools of PtdIns(3,4,5)P3 has long been speculated upon. By using transfected and recombinant protein probes for PtdIns(3,4,5)P3, we show that PtdIns(3,4,5)P3 is enriched in the nuclear envelope and early endosomes. By exploiting an inducible dimerisation device to recruit Akt to these compartments, we demonstrate that Akt can be locally activated in a PtdIns(3,4,5)P3-dependent manner and has the potential to phosphorylate compartmentally localised downstream substrates. This could be an important mechanism to regulate Akt isoform substrate specificity or influence the timing and duration of PI3K pathway signalling. Defects in phosphoinositide metabolism and localisation are known to contribute to cancer, suggesting that interactions at subcellular compartments might be worthwhile targets for therapeutic intervention.

Selection to outsmart the germs: The evolution of disease recognition and social cognition.

The emergence of providing care to diseased conspecifics must have been a turning point during the evolution of hominin sociality. On a population level, care may have minimized the costs of socially transmitted diseases at a time of increasing social complexity, although individual care-givers probably incurred increased transmission risks. We propose that care-giving likely originated within kin networks, where the costs may have been balanced by fitness increases obtained through caring for ill kin. We test a novel hypothesis of hominin cognitive evolution in which disease may have selected for the cognitive ability to recognize when a conspecific is infected. Because diseases may produce symptoms that are likely detectable via the perceptual-cognitive pathways integral to social cognition, we suggest that disease recognition and social cognition may have evolved together. Using agent-based modeling, we test 1) under what conditions disease can select for increasing disease recognition and care-giving among kin, 2) whether providing care produces greater selection for cognition than an avoidance strategy, and 3) whether care-giving alters the progression of the disease through the population. The greatest selection was produced by diseases with lower risks to the care-giver and prevalences low enough not to disrupt the kin networks. When care-giving and avoidance strategies were compared, only care-giving reduced the severity of the disease outbreaks and subsequent population crashes. The greatest selection for increased cognitive abilities occurred early in the model runs when the outbreaks and population crashes were most severe. Therefore, over the course of human evolution, repeated introductions of novel diseases into naïve populations could have produced sustained selection for increased disease recognition and care-giving behavior, leading to the evolution of increased cognition, social complexity, and, eventually, medical care in humans. Finally, we lay out predictions derived from our disease recognition hypothesis that we encourage paleoanthropologists, bioarchaeologists, primatologists, and paleogeneticists to test.

The gestural repertoire of the wild bonobo (Pan paniscus): a mutually understood communication system.

In animal communication, signallers and recipients are typically different: each signal is given by one subset of individuals (members of the same age, sex, or social rank) and directed towards another. However, there is scope for signaller-recipient interchangeability in systems where most signals are potentially relevant to all age-sex groups, such as great ape gestural communication. In this study of wild bonobos (Pan paniscus), we aimed to discover whether their gestural communication is indeed a mutually understood communicative repertoire, in which all individuals can act as both signallers and recipients. While past studies have only examined the expressed repertoire, the set of gesture types that a signaller deploys, we also examined the understood repertoire, the set of gestures to which a recipient reacts in a way that satisfies the signaller. We found that most of the gestural repertoire was both expressed and understood by all age and sex groups, with few exceptions, suggesting that during their lifetimes all individuals may use and understand all gesture types. Indeed, as the number of overall gesture instances increased, so did the proportion of individuals estimated to both express and understand a gesture type. We compared the community repertoire of bonobos to that of chimpanzees, finding an 88 % overlap. Observed differences are consistent with sampling effects generated by the species' different social systems, and it is thus possible that the repertoire of gesture types available to Pan is determined biologically.

Does social environment influence learning ability in a family-living lizard?

Early developmental environment can have profound effects on individual physiology, behaviour, and learning. In birds and mammals, social isolation during development is known to negatively affect learning ability; yet in other taxa, like reptiles, the effect of social isolation during development on learning ability is unknown. We investigated how social environment affects learning ability in the family-living tree skink (Egernia striolata). We hypothesized that early social environment shapes cognitive development in skinks and predicted that skinks raised in social isolation would have reduced learning ability compared to skinks raised socially. Offspring were separated at birth into two rearing treatments: (1) raised alone or (2) in a pair. After 1 year, we quantified spatial learning ability of skinks in these rearing treatments (N = 14 solitary, 14 social). We found no effect of rearing treatment on learning ability. The number of skinks to successfully learn the task, the number of trials taken to learn the task, the latency to perform the task, and the number of errors in each trial did not differ between isolated and socially reared skinks. Our results were unexpected, yet the facultative nature of this species' social system may result in a reduced effect of social isolation on behaviour when compared to species with obligate sociality. Overall, our findings do not provide evidence that social environment affects development of spatial learning ability in this family-living lizard.

Living in stable social groups is associated with reduced brain size in woodpeckers (Picidae).

Group size predicts brain size in primates and some other mammal groups, but no such relationship has been found in birds. Instead, stable pair-bonding and bi-parental care have been identified as correlates of larger brains in birds. We investigated the relationship between brain size and social system within the family Picidae, using phylogenetically controlled regression analysis. We found no specific effect of duration or strength of pair-bonds, but brain sizes were systematically smaller in species living in long-lasting social groups of larger sizes. Group-living may only present a cognitive challenge in groups in which members have individually competitive relationships; we therefore propose that groups functioning for cooperative benefit may allow disinvestment in expensive brain tissue.

Chimpanzee uses manipulative gaze cues to conceal and reveal information to foraging competitor.

Tactical deception has been widely reported in primates on a functional basis, but details of behavioral mechanisms are usually unspecified. We tested a pair of chimpanzees (Pan troglodytes) in the informed forager paradigm, in which the subordinate saw the location of hidden food and the dominant did not. We employed cross-correlations to examine temporal contingencies between chimpanzees' behavior: specifically how the direction of the subordinate's gaze and movement functioned to manipulate the dominant's searching behavior through two tactics, withholding, and misleading information. In Experiment 1, not only did the informed subordinate tend to stop walking toward a single high value food, but she also refrained from gazing toward it, thus, withholding potentially revealing cues from her searching competitor. In a second experiment, in which a moderate value food was hidden in addition to the high value food, whenever the subordinate alternated her gaze between the dominant and the moderate value food, she often paused walking for 5 s; this frequently recruited the dominant to the inferior food, functioning as a "decoy." The subordinate flexibly concealed and revealed gaze toward a goal, which suggests that not only can chimpanzees use visual cues to make predictions about behavior, but also that chimpanzees may understand that other individuals can exploit their gaze direction. These results substantiate descriptive reports of how chimpanzees use gaze to manipulate others, and to our knowledge are the first quantitative data to identify behavioral mechanisms of tactical deception. RESEARCH HIGHLIGHTS: Cross correlations show a subordinate chimpanzee tactically deceived a dominant by not gazing toward a valuable food (withholding), and recruiting to a "decoy" food (misleading). Chimpanzees understand that others can exploit their gaze direction.

Spatio-temporal complexity of chimpanzee food: How cognitive adaptations can counteract the ephemeral nature of ripe fruit.

Ecological complexity has been proposed to play a crucial role in primate brain-size evolution. However, detailed quantification of ecological complexity is still limited. Here we assess the spatio-temporal distribution of tropical fruits and young leaves, two primary chimpanzee (Pan troglodytes) foods, focusing on the predictability of their availability in individual trees. Using up to 20 years of information on monthly availability of young leaf, unripe and ripe fruit in plant species consumed by chimpanzees from tropical forests in East, Central, and West Africa, we estimated: (1) the forest-wide frequency of occurrence of each food type and (2) the predictability of finding ripe fruit-bearing trees, focusing on the timing, frequency, and amount of ripe fruit present. In all three forests, at least half of all encountered trees belonged to species that chimpanzees were known to feed on. However, the proportion of these trees bearing young leaves and fruit fluctuated widely between months. Ripe fruit was the most ephemeral food source, and trees that had more than half of their crown filled were at least nine times scarcer than other trees. In old growth forests only one large ripe fruit crop was on average encountered per 10 km. High levels of inter-individual variation in the number of months that fruit was present existed, and in some extreme cases individuals bore ripe fruit more than seven times as often as conspecifics. Some species showed substantially less variation in such ripe fruit production frequencies and fruit quantity than others. We hypothesize that chimpanzees employ a suite of cognitive mechanisms, including abilities to: (1) generalize or classify food trees; (2) remember the relative metrics of quantity and frequency of fruit production across years; and (3) flexibly plan return times to feeding trees to optimize high-energy food consumption in individual trees, and efficient travel between them. Am. J. Primatol. 78:626-645, 2016. © 2016 Wiley Periodicals, Inc.

Refractory Ventricular Fibrillation Successfully Cardioverted With Dual Sequential Defibrillation.

BACKGROUND: Current guidelines for the treatment of adult patients in cardiac arrest are supplied by the American Heart Association through basic life support and advanced cardiovascular life support (ACLS) provider courses. When treatments defined by the ACLS guidelines are unsuccessful in terminating a lethal dysrhythmia, the use of alternative strategies may prove useful. In this case, two defibrillators were used to deliver a greater than normal energy waveform over an extended time interval to return a patient to a normal sinus rhythm. CASE REPORT: A 56-year-old woman presented to the emergency department with complaints of chest pain, nausea, and vomiting. The patient's initial work-up, including an electrocardiogram and cardiac troponin, did not show evidence of acute ischemia, and she was admitted to the observation unit for further evaluation. While in the emergency department, the patient developed ventricular fibrillation, and ACLS was initiated. After four unsuccessful defibrillation attempts, a second defibrillator was placed on the patient, and the two were activated almost simultaneously. The patient had immediate return of spontaneous circulation, underwent cardiac catheterization, and was discharged home 1 week later. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case shows that dual sequential defibrillation may be a successful method for terminating refractory ventricular fibrillation. Further investigation on cardiac resuscitation should be conducted to standardize the dual sequential defibrillation delivery procedure. Until such guidelines are established, physicians should take this treatment into consideration when standard ACLS measures have failed to successfully terminate refractory ventricular fibrillation.