David Spiegel

Bio: David Spiegel is an academic researcher from Stanford University. The author has contributed to research in topics: Medicine & Breast cancer. The author has an hindex of 106, co-authored 733 publications receiving 46276 citations. Previous affiliations of David Spiegel include Tel Aviv University & University of Adelaide.

Chemical Probes Reveal an Extraseptal Mode of Cross-Linking in Staphylococcus aureus

Abstract: Staphylococcus aureus is an important human pathogen and a model organism for studying cell wall synthesis in Gram-positive cocci. The prevailing model of cell wall biogenesis in cocci holds that peptidoglycan synthesis (i.e., transglycosylation and cross-linking) is restricted spatially to the septal cross-wall and temporally to cell division. Previously, we developed a method for visualizing cross-linking in S. aureus using fluorescently tagged mimics of the endogenous substrate of penicillin-binding proteins (PBPs). These probes are incorporated into the cell wall of S. aureus specifically by PBP4, allowing localization of the enzyme's cross-linking activity in vivo with precise spatial and temporal resolution. Here, using this methodology, we have discovered that PBP4 is active not only at the septum, but unexpectedly at the peripheral wall as well. These results challenge the long-held belief that peptidoglycan synthesis is restricted to the septum in spherical bacteria, and instead indicate the presence of two spatiotemporally distinct modes of cross-linking in S. aureus: one at the septum during cell division, and another at the peripheral wall between divisions.

Relateralizing hypnosis: or, have we been barking up the wrong hemisphere?

Abstract: Research and theory over the past couple decades have suggested that the right cerebral hemisphere might be the focus of brain activity during hypnosis. Recent evidence from electrodermal responding, visual event-related potentials, and Stroop interference, however, can make a case for a role of the left hemisphere in some hypnotic phenomena. Although hemispheric activation on hypnotic challenge may depend in large part on the kind of task the challenge might involve, several general aspects of hypnosis might be more appropriately seen as left-rather than right-hemisphere brain functions. Among these are concentrated attentional focus and the role of language in the establishment of hypnotic reality. A left-hemisphere theory of hypnosis is discussed in light of recent findings and theories about a left-hemisphere basis for synthetic or generational capabilities (Corballis, 1991) and a neuro-evolutionary model of a left-hemisphere dopaminergic activation system for the implementation of predetermined motor programs (Tucker & Williamson, 1984).

Dissociative Symptoms and Cortisol Responses to Recounting Traumatic Experiences Among Childhood Sexual Abuse Survivors with PTSD

Abstract: This study examined dissociative symptoms in relation to changes in evening salivary cortisol levels after recounting traumatic experiences among 49 women with PTSD for child sexual abuse (CSA). Each woman was interviewed to describe her sexual abuse and was assessed on acute dissociative symptoms in response to a recent stressful event in the previous month. Salivary cortisol was assessed during the interview using saliva samples taken immediately before and after the interview. Changes in cortisol levels were measured at one hour, 24 hours, and 48 hours after the interview. Acute dissociative symptoms were related to salivary cortisol levels 24 hours after the interview, with high dissociators showing elevated levels compared to low dissociators. These results suggest that dissociative symptoms in response to recent life stress are associated with cortisol dysregulation among women with PTSD for CSA.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

The Benefits of Being Present: Mindfulness and Its Role in Psychological Well-Being

Abstract: Mindfulness is an attribute of consciousness long believed to promote well-being. This research provides a theoretical and empirical examination of the role of mindfulness in psychological well-being. The development and psychometric properties of the dispositional Mindful Attention Awareness Scale (MAAS) are described. Correlational, quasi-experimental, and laboratory studies then show that the MAAS measures a unique quality of consciousness that is related to a variety of well-being constructs, that differentiates mindfulness practitioners from others, and that is associated with enhanced selfawareness. An experience-sampling study shows that both dispositional and state mindfulness predict self-regulated behavior and positive emotional states. Finally, a clinical intervention study with cancer patients demonstrates that increases in mindfulness over time relate to declines in mood disturbance and stress. Many philosophical, spiritual, and psychological traditions emphasize the importance of the quality of consciousness for the maintenance and enhancement of well-being (Wilber, 2000). Despite this, it is easy to overlook the importance of consciousness in human well-being because almost everyone exercises its primary capacities, that is, attention and awareness. Indeed, the relation between qualities of consciousness and well-being has received little empirical attention. One attribute of consciousness that has been much-discussed in relation to well-being is mindfulness. The concept of mindfulness has roots in Buddhist and other contemplative traditions where conscious attention and awareness are actively cultivated. It is most commonly defined as the state of being attentive to and aware of what is taking place in the present. For example, Nyanaponika Thera (1972) called mindfulness “the clear and single-minded awareness of what actually happens to us and in us at the successive moments of perception” (p. 5). Hanh (1976) similarly defined mindfulness as “keeping one’s consciousness alive to the present reality” (p. 11). Recent research has shown that the enhancement of mindfulness through training facilitates a variety of well-being outcomes (e.g., Kabat-Zinn, 1990). To date, however, there has been little work examining this attribute as a naturally occurring characteristic. Recognizing that most everyone has the capacity to attend and to be aware, we nonetheless assume (a) that individuals differ in their propensity or willingness to be aware and to sustain attention to what is occurring in the present and (b) that this mindful capacity varies within persons, because it can be sharpened or dulled by a variety of factors. The intent of the present research is to reliably identify these inter- and intrapersonal variations in mindfulness, establish their relations to other relevant psychological constructs, and demonstrate their importance to a variety of forms of psychological well-being.

Standards of Medical Care in Diabetes

Abstract: XI. STRATEGIES FOR IMPROVING DIABETES CARE D iabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes. These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed. For more detailed information, refer to Bode (Ed.): Medical Management of Type 1 Diabetes (1), Burant (Ed): Medical Management of Type 2 Diabetes (2), and Klingensmith (Ed): Intensive Diabetes Management (3). The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.