GlideScope视频喉镜和Macintosh直接喉镜在颈椎损伤患者气管插管中的应用比较

目的:比较GlideScope视频喉镜(加拿大Saturn生物技术有限公司)和普通直接喉镜在颈椎损伤患者气管插管中的难易,及两种工具插管对血液动力学的影响。方法:拟在经口气管插管全身麻醉下行择期手术的患者40例,ASAI级,年龄18～60岁,随机分为G组和M组(n=20)。常规麻醉诱导后,手法制动头颈部,G组采用GlideScope视频喉镜,M组用Macintosh直接喉镜行气管插管。分析比较两组声门暴露情况(Cormark-Lehane分级)以及暴露时间,试插次数,失败例数,有无助手辅助,插管前后心率与收缩压乘积(RPP)变化。结果:与M组比较,G组声门暴露情况较好,但暴露时间显著延长(P<0.05)。M组需要助手辅助及插管失败的比例均高于G组。两组RPP的变化在各个时点无显著差别。结论:在为颈椎损伤患者气管插管中,GlideScope视频喉镜能够更好的显露声门,降低插管难度,提高插管的成功率。     

The dangers of multi‐male groupings: trauma and healing in cercopithecoid monkeys from Cameroon

This study examines the potential linkage between social organization and trauma in a sample of cercopithecids from Cameroon. Skeletal trauma is described in a museum collection of eight sympatric monkey species. Macroscopic analysis was carried out on a total of 139 complete skeletons of mangabeys, colobines and guenons. Species in multi‐male groups were found to have higher fracture frequencies than those in uni‐male groups. These higher frequencies may be related to intra‐specific male–male aggression; however, similarities in fracture patterning between males and females in multi‐male groups suggest that other factors may be involved. Although fracture etiology may not be identified with certainty, this study suggests that predation may indirectly be a cause of traumatic injuries in those species of cercopithecid monkeys displaying multi‐male social organizations. The data presented also highlight the utility of museum collections as an additional resource in analyses of primate behavior, demonstrating that behavioral information does not die when the animal does. Am. J. Primatol. 71:567–573, 2009. © 2009 Wiley‐Liss, Inc.     

Microdialysis of dopamine interpreted with quantitative model incorporating probe implantation trauma

Although microdialysis is widely used to sample endogenous and exogenous substances in vivo, interpretation of the results obtained by this technique remains controversial. The goal of the present study was to examine recent criticism of microdialysis in the specific case of dopamine (DA) measurements in the brain extracellular microenvironment. The apparent steady-state basal extracellular concentration and extraction fraction of DA were determined in anesthetized rat striatum by the concentration difference (no-net-flux) microdialysis technique. A rate constant for extracellular clearance of DA calculated from the extraction fraction was smaller than the previously determined estimate by fast-scan cyclic voltammetry for cellular uptake of DA. Because the relatively small size of the voltammetric microsensor produces little tissue damage, the discrepancy between the uptake rate constants may be a consequence of trauma from microdialysis probe implantation. The trauma layer has previously been identified by histology and proposed to distort measurements of extracellular DA levels by the no-net-flux method. To address this issue, an existing quantitative mathematical model for microdialysis was modified to incorporate a traumatized tissue layer interposed between the probe and surrounding normal tissue. The tissue layers are hypothesized to differ in their rates of neurotransmitter release and uptake. A post-implantation traumatized layer with reduced uptake and no release can reconcile the discrepancy between DA uptake measured by microdialysis and voltammetry. The model predicts that this trauma layer would cause the DA extraction fraction obtained from microdialysis in vivo calibration techniques, such as no-net-flux, to differ from the DA relative recovery and lead to an underestimation of the DA extracellular concentration in the surrounding normal tissue.     

Traumatic Brain Injury Increases β-Amyloid Peptide 1-42 in Cerebrospinal Fluid

Abstract: The β-amyloid peptides, Aβ1-42 and Aβ1-40, were quantified in ventricular CSF taken daily for up to 3 weeks from six individuals with severe traumatic brain injury (TBI). There was considerable interindividual variability in the levels of Aβ peptides, but in general Aβ1-42 levels equalled or exceeded those of Aβ1-40. Averaging the daily totals of our trauma cohort revealed that the levels of Aβ1-42 and Aβ1-40 rose after injury, peaking in the first week and then declining toward control levels over the next 2 weeks. Aβ1-42 levels were on average two to three times higher in the trauma cohort than in CSF from nontrauma samples. Compared with nontrauma samples, the Aβ1-40/Aβ1-42 ratio decreased about fivefold in the trauma patients, further indicative of increased Aβ1-42 levels. The ratio remained low at all time points studied. No change was measured in the levels of β-amyloid precursor protein during the same interval. These results suggest that Aβ1-42 becomes elevated in the CSF after severe brain trauma.     

Stress protein synthesis and accumulation after traumatic injury of crayfish CNS

By several days after a crush injury of crayfish CNS, the wound site heals. Changes in protein synthesis and accumulation occur at the lesion site and nearby. During the first few hours, synthesis of 35, 70, 90, and 150 kDa proteins is induced in the injured tissue. By one day, the relative amounts of 70–90 kDa proteins increase dramatically, particularly at the crush site and adjacent to it. The 70 kDa proteins, which are related to mammalian stress proteins (SPs), remain elevated for at least one month in the traumatized region or nearby. The crushed tissue contains an SP70 isoform not present in its uncrushed counterpart. These biochemical changes may reflect the cellular changes that accompany wound healing and/or a cellular stress response to compensate for the lesion. Since similar adaptations occur in the mammalian CNS, they may represent a phylogenetically conserved attempt to retard or repair CNS tissue deterioration.     

The impact of early adversity and education on genetic and brain morphological predictors of cognitive ability

Cognitive ability is a strong predictor of occupational achievement, quality of life and physical health. While variation in cognition is strongly heritable and has been robustly associated with early environment and brain morphology, little is known about how these factors combine and interact to explain this variation in cognition. To address this, we modelled the relationship between common genetic variation, grey matter volume, early life adversity and education and cognitive ability in a UK Biobank sample of N = 5237 individuals using structural equation modelling. We tested the hypotheses that total grey matter volume would mediate the association between genetic variation and cognitive ability, and that early life adversity and educational attainment would moderate this relationship. Common genetic variation, grey matter volume and early life adversity were each significant predictors in the model, explaining ~15% of variation in cognitive ability. Contrary to our hypothesis, grey matter volume did not mediate the relation between genetic variation and cognition performance. Neither did early life adversity or educational attainment moderate this relation, although educational attainment was observed to moderate the relationship between grey matter volume and cognitive performance. We interpret these findings in terms of the modest explanatory value of currently estimated polygenic scores accounting for variation in cognitive performance (~5%), making potential mediating and moderating variables difficult to confirm.     

Developmental correlates of crown component asymmetry and occlusal discrepancy

To improve our understanding of dental asymmetry, more anatomically discriminating measurements than maximum crown dimensions were used. The relation between antimeres and opponents in permanent first molar teeth of 192 twins were studied with respect to crown component measures. Several statistical methods were used to describe asymmetry and discrepancy of occluding units to correlate with developmental stress indicators such as zygosity, birth weight, and congenital disease. To varying degrees, developmental correlates are found to be associated with asymmetry. The amount of occlusal discrepancy seems to be a direct function of bilateral asymmetry. Heterogeneity of MZ-DZ total (among plus within pair) variances occurs fairly consistently for asymmetry but not for discrepancy, implying differential environmental influences between zygosities regarding asymmetry. Genetic variance estimates, designed to be unbiased by differences in environmental variances, are significant for cusp size but not for asymmetry. Our results suggest that asymmetry at the individual cusp level may be an indicator of developmental disruption and that environmental effects, particularly prenatal, may be greater for antimeric units than for occluding units.     

A study of microwear on chimpanzee molars: Implications for dental microwear analysis

Recent investigations of dental microwear have shown that such analyses may ultimately provide valuable information about the diets of fossil species. However, no background information about intraspecific variability of microwear patterns has been available until now. This study presents the results of an SEM survey of microwear patterns found on occlusal enamel of chimpanzee molars. Methods of pattern analysis are described. Selected sites on the occlusal surface included shearing, grinding, and puncture-crushing surfaces formed by both phases of the power stroke of mastication. The microwear patterns found in this sample of chimpanzees showed a high degree of regularity. However, certain parameters such as relative pit-to-striation frequencies, feature density, striation length, and pit diameter were significantly affected by facet type and molar position. Sex and age of individuals also influenced some microwear parameters, but due to the small sample size these findings are considered to be preliminary. These results show that microwear within a single species may vary because of factors that are due more to biomechanics than to diet. The study also supplies some metrical estimates of “normal” pattern variability due to functional and morphological influences. These estimates should provide a useful baseline for assessing the significance of microwear pattern differences that may be found between species of differing diets.     

Inhibition of IL-17 prevents the progression of traumatic heterotopic ossification

Traumatic heterotopic ossification (HO) is the abnormal formation of bone in soft tissues as a consequence of injury. However, the pathological mechanisms leading to traumatic HO remain unknown. Here, we report that aberrant expression of IL-17 promotes traumatic HO formation by activating β-catenin signalling in mouse model. We found that elevated IL-17 and β-catenin levels are correlated with a high degree of HO formation in specimens from patients and HO animals. We also show that IL-17 initiates and promotes HO progression in mice. Local injection of an IL-17 neutralizing antibody attenuates ectopic bone formation in a traumatic mouse model. IL-17 enhances the osteoblastic differentiation of mesenchymal stem cells (MSCs) by activating β-catenin signalling. Moreover, inhibition of IL-17R or β-catenin signalling by neutralizing antibodies or drugs prevents the osteogenic differentiation of isolated MSCs and decreases HO formation in mouse models. Together, our study identifies a novel role for active IL-17 as the inducer and promoter of ectopic bone formation and suggests that IL-17 inhibition might be a potential therapeutic target in traumatic HO.     

A Talent for Life: Reflections on Human Vulnerability and Resilience

This article explores the limitations of the dominant psychological trauma model. Drawing on the experiences and the aftermaths of chronic ‘states of emergency ‘ among shantytown families in rural Northeast Brazil, among hunted street kids in urban Brazil, and among revolutionaries and warriors of different political stripes following the anti-apartheid struggle in South Africa, I identify several features of human resilience, the sources of strength, toughness, hardiness, and relative immunity from personal and psychological collapse that we have come to associate with exposure to a variety of human calamities. We need to rethink our notions of trauma, violence and its sequalae.