The oral bacterial microbiome encompasses approximately 700 commonly occurring phylotypes, approximately half of which can be present at any time in any individual. These bacteria are largely ...indigenous to the oral cavity; this limited habitat range suggests that interactions between the various phylotypes, and between the phylotypes and their environment, are crucial for their existence. Molecular cataloging has confirmed many basic observations on the composition of the oral microbiome that were formulated well before ribosomal RNA‐based systematics, but the power and the scope of molecular taxonomy have resulted in the discovery of new phylotypes and, more importantly, have made possible a level of bacterial community analysis that was unachievable with classical methods. Bacterial community structure varies with location within the mouth, and changes in community structure are related to disease initiation and disease progression. Factors that influence the formation and the evolution of communities include selective adherence to epithelial or tooth surfaces, specific cell‐to‐cell binding as a driver of early community composition, and interorganismal interaction leading to alteration of the local environment, which represents the first step on the road to oral disease. A comprehensive understanding of how these factors interact to drive changes in the composition of the oral microbial community can lead to new strategies for the inhibition of periodontal diseases and dental caries.
Many cancer centers offer acupuncture services. To date, a comprehensive systematic review of acupuncture in cancer care has not been conducted. The purpose of this review was to evaluate the ...efficacy of acupuncture for symptom management in patients with cancer.
Medline, Embase, CINAHL, Cochrane (all databases), Scopus, and PubMed were searched from inception through December 2011 for prospective randomized clinical trials (RCT) evaluating acupuncture for symptom management in cancer care. Only studies involving needle insertion into acupuncture points were included. No language limitations were applied. Studies were assessed for risk of bias (ROB) according to Cochrane criteria. Outcomes by symptom were designated as positive, negative, or unclear.
A total of 2,151 publications were screened. Of those, 41 RCTs involving eight symptoms (pain, nausea, hot flashes, fatigue, radiation-induced xerostomia, prolonged postoperative ileus, anxiety/mood disorders, and sleep disturbance) met all inclusion criteria. One positive trial of acupuncture for chemotherapy-induced nausea and vomiting had low ROB. Of the remaining studies, eight had unclear ROB (four positive, three negative, and one with unclear outcomes). Thirty-three studies had high ROB (19 positive, 11 negative, and three with both positive and negative outcomes depending on the symptom).
Acupuncture is an appropriate adjunctive treatment for chemotherapy-induced nausea/vomiting, but additional studies are needed. For other symptoms, efficacy remains undetermined owing to high ROB among studies. Future research should focus on standardizing comparison groups and treatment methods, be at least single-blinded, assess biologic mechanisms, have adequate statistical power, and involve multiple acupuncturists.
Sleep exerts many effects on mammalian forebrain networks, including homeostatic effects on both synaptic strengths and firing rates. We used large-scale recordings to examine the activity of neurons ...in the frontal cortex of rats and first observed that the distribution of pyramidal cell firing rates was wide and strongly skewed toward high firing rates. Moreover, neurons from different parts of that distribution were differentially modulated by sleep substates. Periods of nonREM sleep reduced the activity of high firing rate neurons and tended to upregulate firing of slow-firing neurons. By contrast, the effect of REM was to reduce firing rates across the entire rate spectrum. Microarousals, interspersed within nonREM epochs, increased firing rates of slow-firing neurons. The net result of sleep was to homogenize the firing rate distribution. These findings are at variance with current homeostatic models and provide a novel view of sleep in adjusting network excitability.
•Pyramidal cell firing rates are widely distributed and skewed toward high firing rates•Neurons from opposite ends of that distribution are oppositely modulated by sleep•Sleep stages have systematically varying effects on neurons of different firing rates•REM, nonREM, and microarousal effects cooperate to create the sleep homeostatic effect
Watson et al. reveal a new form of regulation of neural activity by sleep. The firing rates of fast- and slow-firing neurons are homogenized over sleep. This effect is due to contributions from REM, nonREM, and sleep microarousals.
Growth of oral bacteria in situ requires adhesion to a surface because the constant flow of host secretions thwarts the ability of planktonic cells to grow before they are swallowed. Therefore, oral ...bacteria evolved to form biofilms on hard tooth surfaces and on soft epithelial tissues, which often contain multiple bacterial species. Because these biofilms are easy to study, they have become the paradigm of multispecies biofilms. In this Review we describe the factors involved in the formation of these biofilms, including the initial adherence to the oral tissues and teeth, cooperation between bacterial species in the biofilm, signalling between the bacteria and its role in pathogenesis, and the transfer of DNA between bacteria. In all these aspects distance between cells of different species is integral for oral biofilm growth.
Summary Osteoarthritis is a major source of pain, disability, and socioeconomic cost worldwide. The epidemiology of the disorder is complex and multifactorial, with genetic, biological, and ...biomechanical components. Aetiological factors are also joint specific. Joint replacement is an effective treatment for symptomatic end-stage disease, although functional outcomes can be poor and the lifespan of prostheses is limited. Consequently, the focus is shifting to disease prevention and the treatment of early osteoarthritis. This task is challenging since conventional imaging techniques can detect only quite advanced disease and the relation between pain and structural degeneration is not close. Nevertheless, advances in both imaging and biochemical markers offer potential for diagnosis and as outcome measures for new treatments. Joint-preserving interventions under development include lifestyle modification and pharmaceutical and surgical modalities. Some show potential, but at present few have proven ability to arrest or delay disease progression.
Autism spectrum disorder currently lacks an explanation that bridges cognitive, computational, and neural domains. In the past 5 years, progress has been sought in this area by drawing on Bayesian ...probability theory to describe both social and nonsocial aspects of autism in terms of systematic differences in the processing of sensory information in the brain. The present article begins by synthesizing the existing literature in this regard, including an introduction to the topic for unfamiliar readers. The key proposal is that autism is characterized by a greater weighting of sensory information in updating probabilistic representations of the environment. Here, we unpack further how the hierarchical setting of Bayesian inference in the brain (i.e., predictive processing) adds significant depth to this approach. In particular, autism may relate to finer mechanisms involved in the context-sensitive adjustment of sensory weightings, such as in how neural representations of environmental volatility inform perception. Crucially, in light of recent sensorimotor treatments of predictive processing (i.e., active inference), hypotheses regarding atypical sensory weighting in autism have direct implications for the regulation of action and behavior. Given that core features of autism relate to how the individual interacts with and samples the world around them (e.g., reduced social responding, repetitive behaviors, motor impairments, and atypical visual sampling), the extension of Bayesian theories of autism to action will be critical for yielding insights into this condition.
Plant defense compounds occur in floral nectar, but their ecological role is not well understood. We provide evidence that plant compounds pharmacologically alter pollinator behavior by enhancing ...their memory of reward. Honeybees rewarded with caffeine, which occurs naturally in nectar of Coffea and Citrus species, were three times as likely to remember a learned floral scent as were honeybees rewarded with sucrose alone. Caffeine potentiated responses of mushroom body neurons involved in olfactory learning and memory by acting as an adenosine receptor antagonist. Caffeine concentrations in nectar did not exceed the bees' bitter taste threshold, implying that pollinators impose selection for nectar that is pharmacologically active but not repellent. By using a drug to enhance memories of reward, plants secure pollinator fidelity and improve reproductive success.
We present the main findings of the 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia (AAGA). Incidences were estimated using reports of accidental awareness as the ...numerator, and a parallel national anaesthetic activity survey to provide denominator data. The incidence of certain/probable and possible accidental awareness cases was ∼1:19 600 anaesthetics (95% confidence interval 1:16 700–23 450). However, there was considerable variation across subtypes of techniques or subspecialities. The incidence with neuromuscular block (NMB) was ∼1:8200 (1:7030–9700), and without, it was ∼1:135 900 (1:78 600–299 000). The cases of AAGA reported to NAP5 were overwhelmingly cases of unintended awareness during NMB. The incidence of accidental awareness during Caesarean section was ∼1:670 (1:380–1300). Two-thirds (82, 66%) of cases of accidental awareness experiences arose in the dynamic phases of anaesthesia, namely induction of and emergence from anaesthesia. During induction of anaesthesia, contributory factors included: use of thiopental, rapid sequence induction, obesity, difficult airway management, NMB, and interruptions of anaesthetic delivery during movement from anaesthetic room to theatre. During emergence from anaesthesia, residual paralysis was perceived by patients as accidental awareness, and commonly related to a failure to ensure full return of motor capacity. One-third (43, 33%) of accidental awareness events arose during the maintenance phase of anaesthesia, mostly due to problems at induction or towards the end of anaesthesia. Factors increasing the risk of accidental awareness included: female sex, age (younger adults, but not children), obesity, anaesthetist seniority (junior trainees), previous awareness, out-of-hours operating, emergencies, type of surgery (obstetric, cardiac, thoracic), and use of NMB. The following factors were not risk factors for accidental awareness: ASA physical status, race, and use or omission of nitrous oxide. We recommend that an anaesthetic checklist, to be an integral part of the World Health Organization Safer Surgery checklist, is introduced as an aid to preventing accidental awareness. This paper is a shortened version describing the main findings from NAP5—the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home.
Background The ideal age to introduce egg into the infant diet has been debated for the past 2 decades in the context of rising rates of egg allergy. Objective We sought to determine whether regular ...consumption of egg protein from age 4 to 6 months reduces the risk of IgE-mediated egg allergy in infants with hereditary risk, but without eczema. Methods Infants aged 4 to 6 months were randomly allocated to receive daily pasteurized raw whole egg powder (n = 407) or a color-matched rice powder (n = 413) to age 10 months. All infants followed an egg-free diet and cooked egg was introduced to both groups at age 10 months. The primary outcome was IgE-mediated egg allergy defined by a positive pasteurized raw egg challenge and egg sensitization at age 12 months. Results There was no difference between groups in the percentage of infants with IgE-mediated egg allergy (egg 7.0% vs control 10.3%; adjusted relative risk, 0.75; 95% CI, 0.48-1.17; P = .20). A higher proportion of participants in the egg group stopped taking the study powder because of a confirmed allergic reaction (25 of 407 6.1% compared with 6 of 413 1.5%). Egg-specific IgG4 levels were substantially higher in the egg group at 12 months (median, 1.22 mgA /L vs control 0.07 mgA /L; P < .0001). Conclusions We found no evidence that regular egg intake from age 4 to 6 months substantially alters the risk of egg allergy by age 1 year in infants who are at hereditary risk of allergic disease and had no eczema symptoms at study entry.