The Oral and Maxillofacial Surgery Anesthesia Team Model.

Oral and maxillofacial surgeons have been providing safe anesthesia to their patients using the anesthesia team model; this has allowed access to care for patients that have significant anxiety. The AAOMS strives to maintain the excellent safety record of the anesthesia team model by creating simulation programs in anesthesia, regularly updating the office anesthesia evaluation program, convening anesthesia safety conferences and strengthening the standards in our training programs. Through these efforts, our delivery of anesthesia to our patients will remain safe and effective.

Physician's emerging roles relating to trends in health information technology.

OBJECTIVE: To determine the new roles that physicians will adopt in the near future to adjust to accelerating trends from managed care to outcome-based practice to health care reform to health information technology to the evolving role of health consumers. METHODS: Trends and related developments concerning the changing roles of physicians based on prior literature reviews. RESULTS: Six possible roles, traditional, gatekeeper, coach, navigator, informatician and one voice among many, are discussed in terms of physician's centrality, patient autonomy, decision-making and uncertainty, information seeking, satisfaction and outcomes, particularly those related to compliance. CONCLUSION: A greater understanding of these emerging roles could lead to more efficacious outcomes in our ever changing, increasingly complex medical system. Patients often have little understanding of emerging trends that lead to the development of specialized roles such as hospitalist and navigators and, relatedly, the evolving roles of physicians.

Information seeking and intentions to have genetic testing for hereditary cancers in rural and Appalachian Kentuckians.

CONTEXT: Research is limited regarding the potential of genetic testing for cancer risk in rural Appalachia. PURPOSE: This study examined perceptions of genetic testing in a population sample of Kentuckians, with a focus on Appalachian and rural differences. The goals were to examine cultural and psychosocial factors that may predict intentions to test for hereditary cancer, need for help with information seeking for decision making about genetic testing for hereditary cancer, and amount of help needed with information seeking for decision making about genetic testing for hereditary cancer in this population. METHODS: Analysis of data from a general social survey of adults using random-digit dialing in Kentucky (N = 882). FINDINGS: An ordinal regression found that younger age, having a family history of cancer, and greater worry predicted greater intentions to seek genetic testing. A logistic regression found that having more education, excellent subjective knowledge of genetics, and less worry about cancer predicted less need for help in seeking information about testing. An ordinal regression found that less subjective knowledge of genetics and greater worry predicted greater amount of help needed. CONCLUSIONS: Additional counseling to explain limitations of genetic testing may be needed. Further, those with less knowledge about genetics and more worry about hereditary cancer may have greater need for help with information seeking for decision making, a need that may be further exacerbated by the lack of medical professionals, particularly genetic counselors, who may provide information about genetic testing in rural, Appalachian Kentucky.

The conversational brain: fronto-hippocampal interaction and disconnection.

The paper promotes the view that the alert brain alternates between operating in an action mode, based on frontal lobe function, and a receptive mode, involving cholinergic system activity. Their alternation forms a conversation with the environment. It is hypothesized that competition between the modes centers on control over excitability of neurons in the CA1 field of the hippocampus. Increased excitability enhances the flow of hippocampal output through the subiculum resulting in support for frontal lobe function and the action mode. Decreased excitability, on the other hand, reduces this output and that support, leading to a disconnection between frontal lobes and hippocampus. At the same time, correlated cholinergic activity enhances receptive mode processes, indicated by the occurrence of the hippocampal theta rhythm. It is suggested that the hypothesis provides a conceptual framework for considering various phenomena including REM sleep, schizophrenia, and hypnosis. In REM sleep the receptive mode remains dominant as cholinergic activity supports the hippocampal integration of experience into a composite view of reality. In schizophrenia, the action and receptive modes are not properly coordinated because of a dysfunction in anterior hippocampal output. And hypnosis might be seen as a process in which conditions and suggestions are able to induce in some people a prolonged occurrence of the receptive mode allowing a normal view of reality to be altered.

Troponin C/calmodulin chimeras as erythrocyte plasma membrane Ca2+-ATPase activators.

Calmodulin (CaM) and troponin C (TnC) are EF-hand proteins that play fundamentally different roles in animal physiology. TnC has a very low affinity for the plasma membrane Ca2+-ATPase and is a poor substitute for CaM in increasing the enzyme's affinity for Ca2+ and the rate of ATP hydrolysis. We use a series of recombinant TnC (rTnC)/CaM chimeras to clarify the importance of the CaM carboxyl-terminal domain in the activation of the plasma membrane Ca2+-ATPase. The rTnC/CaM chimera, in which the carboxyl-terminal domain of TnC is replaced by that of CaM, has the same ability as CaM to bind and transmit the signal to Ca2+ sites on the enzyme. There is no further functional gain when the amino-terminal domain is modified to make the rTnC/CaM chimera more CaM-like. To identify which regions of the carboxyl-terminal domain of CaM are responsible for these effects, we constructed the chimeras rTnC/3CaM and rTnC/4CaM, where only one-half of the C-terminal domain of CaM (residues 85-112 or residues 113-148) replaces the corresponding region in rTnC. Neither rTnC/3CaM nor rTnC/4CaM can mimic CaM in its affinity for the enzyme. Nevertheless, with respect to the signal transduction process, rTnC/4CaM, but not rTnC/3CaM, shows the same behaviour as CaM. We conclude that the whole C-terminal domain is required for binding to the enzyme while Ca2+-binding site 4 of CaM bears all the requirements to increase Ca2+ binding at PMCA sites. Such mechanism of binding and activation is distinct from that proposed for most other CaM targets. Furthermore, we suggest that Ala128 and Met124 from CaM site 4 may play a crucial role in discriminating CaM from TnC.

Avoiding versus seeking: the relationship of information seeking to avoidance, blunting, coping, dissonance, and related concepts.

QUESTION: How have theorists and empirical researchers treated the human tendency to avoid discomforting information? DATA SOURCES: A historical review (1890-2004) of theory literature in communication and information studies, coupled with searches of recent studies on uptake of genetic testing and on coping strategies of cancer patients, was performed. STUDY SELECTION: The authors' review of the recent literature included searches of the MEDLINE, PsychInfo, and CINAHL databases between 1992 and summer of 2004 and selective, manual searches of earlier literature. Search strategies included the following subject headings and key words: MeSH headings: Genetic Screening/psychology, Decision Making, Neoplasms/diagnosis/genetics/psychology; CINAHL headings: Genetic Screening, Genetic Counseling, Anxiety, Decision Making, Decision Making/Patient; additional key words: avoidance, worry, monitoring, blunting, cancer. The "Related Articles" function in MEDLINE was used to perform additional "citation pearl" searching. MAIN RESULTS: The assumption that individuals actively seek information underlies much of psychological theory and communication practice, as well as most models of the information-seeking process. However, much research has also noted that sometimes people avoid information, if paying attention to it will cause mental discomfort or dissonance. Cancer information in general and genetic screening for cancer in particular are discussed as examples to illustrate this pattern. CONCLUSION: That some patients avoid knowledge of imminent disease makes avoidance behavior an important area for social and psychological research, particularly with regard to genetic testing.

Genomics--the perfect information-seeking research problem.

The intersection of the genetics era and information age poses unique and daunting challenges for health consumers who may not have the health literacy to keep pace. While rapid advances in genetics research promise enhanced care, the inherent complexities and individualistic nature of genetic information have resulted in a challenging information environment. The technical possibilities for acquiring genomic information are increasing at an exponential pace, as are the scientific advances relating to it. Furthermore, societal reactions to genomics, and possible privacy and discrimination issues, may constitute significant constraints. The health care infrastructure also has its limits, given the severe shortage of qualified cancer genetic counselors and general practitioners who are unprepared to address genetics, creating a demand for creative approaches to service delivery. The combination of individual salience, low health literacy, the consumer movement, and important policy problems, then makes genomics the perfect information seeking research problem.

Dysfunction of the anterior hippocampus: the cause of fundamental schizophrenic symptoms?

Recent evidence suggests there is an association between schizophrenia and dysfunction of the anterior hippocampus. Accordingly, this paper endeavors to show how the fundamental schizophrenic symptoms described by Bleuler might arise from deficiencies in normal hippocampal function. This effort is based on the idea that the hippocampus normally constructs a composite picture or worldview of the environment when conditions are novel or uncertain. Then when conditions become familiar, it influences emotion and behavior to be consistent with that worldview. The anterior hippocampus maintains the emotional component of a worldview through its interaction with the amygdala and hypothalamus, and supports executive frontal lobe activity by way of its output to the nucleus accumbens. From this perspective, the split between affect and cognition in schizophrenia is attributed to a failure of the anterior hippocampus to enforce the emotional component of a worldview allowing emotions to diverge from the cognitive component. The splitting of associations is traced to a failure of anterior hippocampal output to support frontal lobe control over the flow of associations. And a split from reality is seen to arise from a combination of these two failures. The individual ceases to interact with the world because the lack of executive control makes such interaction difficult. Fear and fantasies come to dominate experience because emotions are not adequately controlled.

REM sleep and the development of context memory.

The paper proposes that REM sleep exists to promote the development of a special form of memory. This memory is a composite of many specific experiences in a particular environment. When it is subsequently invoked, it creates a contextual framework, thus it may be called context memory. The development of this kind of memory during waking is limited by the need to focus on salient or relevant experiences and restrict the processing of others. These restrictions include mechanisms that support orienting responses and selective attention to what is relevant. It is argued that during REM sleep, the reduction of noradrenergic activity undermines the restrictive effects of orienting and reduction of frontal lobe activity undermines bias toward relevant events. When their reduction is combined with a high level of cholinergic activity, many recent and associated memories may be activated and merged together, giving rise to some of the bizarre events experienced in dreams. Patterns of their activation can be transmitted to the hippocampus where they become integrated to form context memory. From this perspective, the need for REM sleep is greatest when the individual is most lacking in context memory at the beginning of life, although innate structures in precocious infants may lessen their reliance on the acquisition of context memory. Later in life, the need for REM may increase temporarily if the subject encounters a novel environment and is unprepared to meet its demands. However, REM sleep may also become unadaptive when it begins to perpetuate a context memory that has become infused with negative emotions experienced during depression.

Episodic memory and the hippocampus: another view.

A popular view of the function of the hippocampus maintains that this structure temporarily encodes the neocortical representation of the experience of an episode. It uses the encoding to recreate repeatedly the neocortical representation. It is said that in time the episodic memory becomes consolidated in the neocortex and can be retrieved independent of the hippocampus. This paper is critical of that view and begins by raising four concerns. These include a question of how the hippocampus could encode the rich complexity of neocortical representations in sufficient detail to recreate them. And it observes that some data indicate episodic memories remain dependent on the hippocampus for life. Another view of hippocampal function is presented which addresses these concerns. Basically, this view hypothesizes that the ability to retrieve episodic memories involves the interplay between two modes of hippocampal function. Processes during the theta mode facilitate the development of context memory in the hippocampus and the registration of unique events in the neocortex, but block the influence of context memory upon the neocortex. By contrast, during the non-theta mode, context memory is projected onto the neocortex, creating a contextual framework. It is proposed that the ability to retrieve memory of episodes depends on the development, through contiguity, of associations between the representation of the episode (created during theta) and a contextual framework (evoked during non-theta). From this perspective, the episode does not need to be encoded in the hippocampus, but remains dependent indefinitely on associations formed between the episodic memory in the neocortex and a context memory maintained in hippocampal structures. However, for the associations that enable retrieval to form, the creation of the representation of an episode during theta must be followed quickly by the evocation of a contextual framework. During an extended period of the theta mode as occurs during REM sleep dreaming, these associations cannot usually be formed, resulting in amnesia for most dreams.

Regulation of the RYR1 and RYR2 Ca2+ release channel isoforms by Ca2+-insensitive mutants of calmodulin.

Calmodulin (CaM) may function as a regulatory subunit of ryanodine receptor (RYR) channels, modulating both channel activation and inhibition by Ca2+; however, mechanisms underlying differences in CaM regulation of the RYR isoforms expressed in skeletal muscle (RYR1) and cardiac muscle (RYR2) are poorly understood. Here we use a series of CaM mutants deficient in Ca2+ binding to compare determinants of CaM regulation of the RYR1 and RYR2 isoforms. In submicromolar Ca2+, activation of the RYR1 isoform by each of the single-point CaM mutants was similar to that by wild-type apoCaM, whereas in micromolar Ca2+, RYR1 inhibition by Ca2+CaM was abolished by mutations targeting CaM's C-terminal Ca2+ sites. In contrast to the RYR1, no activation of the cardiac RYR2 isoform by wild-type CaM was observed, but rather CaM inhibited the RYR2 at all Ca2+ concentrations (100 nM to 1 mM). Consequently, whereas the apparent Ca2+ sensitivity of the RYR1 isoform was enhanced in the presence of CaM, the RYR2 displayed the opposite response (RYR2 Ca2+ EC50 increased 7-10-fold in the presence of 5 microM wild-type CaM). CaM inhibition of the RYR2 was nonetheless abolished by each of four mutations targeting individual CaM Ca2+ sites. Furthermore, a mutant CaM deficient in Ca2+ binding at all four Ca2+ sites significantly activated the RYR2 and acted as a competitive inhibitor of RYR2 regulation by wild-type Ca2+CaM. We conclude that Ca2+ binding to CaM determines the effect of CaM on both RYR1 and RYR2 channels and that isoform differences in CaM regulation reflect the differential tuning of Ca2+ binding sites on CaM when bound to the different RYRs. These results thus suggest a novel mechanism by which CaM may contribute to functional diversity among the RYR isoforms.