Left Frontoparietal Control Network Connectivity Moderates the Effect of Amyloid on Cognitive Decline in Preclinical Alzheimer's Disease: The A4 Study.

BACKGROUND: Stronger resting-state functional connectivity of the default mode and frontoparietal control networks has been associated with cognitive resilience to Alzheimer's disease related pathology and neurodegeneration in smaller cohort studies. OBJECTIVES: We investigated whether these networks are associated with longitudinal CR to AD biomarkers of beta-amyloid (Aß). DESIGN: Longitudinal mixed. SETTING: The Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) study and its natural history observation arm, the Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) study. PARTICIPANTS: A sample of 1,021 cognitively unimpaired older adults (mean age = 71.2 years [SD = 4.7 years], 61% women, 42% APOEε4 carriers, 52% Aß positive). MEASUREMENTS: Global cognitive performance (Preclinical Alzheimer's Cognitive Composite) was assessed over an average 5.4 year follow-up period (SD = 2 years). Cortical Aß and functional connectivity (left and right frontoparietal control and default mode networks) were estimated from fMRI and PET, respectively, at baseline. Covariates included baseline age, APOEε4 carrier status, years of education, adjusted gray matter volume, head motion, study group, cumulative treatment exposure, and cognitive test version. RESULTS: Mixed effects models revealed that functional connectivity of the left frontoparietal control network moderated the negative effect of Aß on cognitive change (p = .025) such that stronger connectivity was associated with reduced Aß-related cognitive decline. CONCLUSIONS: Our results demonstrate a potential protective effect of functional connectivity in preclinical AD, such that stronger connectivity in this network is associated with slower Aß-related cognitive decline.

Experiences of Multidisciplinary Working: Perspectives from the Wessex Ghana Stroke Partnership.

INTRODUCTION: Substantial gaps remain in our understanding of stroke in Africa as well as in stroke care, practice and policy on the continent. The effective organization of preventative, therapeutic and rehabilitative stroke services continue to be challenging in many African countries. METHODOLOGY: In this article we define the nature, function and benefits of effective multidisciplinary team (MDT) working. The experiences and perspectives of members of the MDT were collated by focus group discussions as well as individual and country specific contributions. RESULTS: The experiences and perspectives of multidisciplinary team members from the United Kingdom and Ghana implementing these practices at the first stroke unit in Korle Bu Teaching Hospital, Accra, with a transparent discussion of successes and challenges faced throughout development of the service, is presented. MDT working has improved outcomes for patients and families who use the services, including encouraging better shared treatment planning and compliance. More stroke rehabilitation services are provided than previously, including greater self-management education and better secondary prevention care. CONCLUSION: It is hoped that this article will provide an inspirational model for others working to provide stroke care in low-resource settings in Africa and worldwide.

INTRODUCTION: Des lacunes substantielles subsistent dans notre compréhension de l'accident vasculaire cérébral en Afrique ainsi que dans les pratiques et politiques sur le continent. L'organisation efficace des services de prévention, de traitement et de réadaptation des AVC reste un défi dans de nombreux pays africains. MÉTHODOLOGIE: Dans cet article, nous définissons la nature, la fonction et les avantages d'une équipe multidisciplinaire efficace (PCT).Les expériences et les points de vue des membres de la PCT ont été recueillis par des discussions de groupes de réflexion ainsi que contributions individuelles et spécifiques à chaque pays. RÉSULTATS: Les expériences et les perspectives des membres d'équipes multidisciplinaires du Royaume-Uni et du Ghana, qui ont mis en œuvre ces pratiques dans la première unité d'AVC du de l'hôpital universitaire Korle Bu, à Accra, avec une discussion transparente des succès et des défis rencontrés tout au long du développement du service, sont présentées. Le travail de la PCT a amélioré les résultats pour les patients et les familles qui utilisent les services, notamment en encourageant un meilleur partage du traitement, l'organisation et la complaisance. Davantage de services de réadaptation après un AVC sont fournis plus qu'auparavant, y compris une meilleure éducation à l'autogestion et de meilleurs soins de prévention secondaire. CONCLUSION: Nous espérons que cet article constituera un modèle inspirant pour d'autres personnes travaillant à la prise en charge d'AVC dans des contextes à faibles ressources en Afrique et dans le monde. Mots clés: Unité de expériences, multidisciplinaire, Ghana, partenariat.

Effects of systematically varied thiourethane-functionalized filler concentration on polymerization behavior and relevant clinical properties of dental composites.

Introduction of thiourethane (TU) oligomer to resin-based dental restorative materials reduces stress and improves fracture toughness without compromising conversion. Localization of TU at the resin-filler interface via silanization procedures may lead to more substantial stress reduction and clinical property enhancements. The objective of this study was to evaluate composite properties as a function of TU-functionalized filler concentration. TU oligomers were synthesized using click-chemistry techniques and subsequently silanized to barium glass filler. Resin-based composites were formulated using varying ratios of TU-functionalized filler and conventional methacrylate-silanized barium filler. Material property testing included thermogravimetric analysis, real-time polymerization kinetics and depth of cure, polymerization stress, stress relaxation and fracture toughness. Clinical property testing included water sorption/solubility, composite paste viscosity, and gloss and surface roughness measured before and after subjecting the samples to 6 h of continuous tooth brushing in a custom-built apparatus using a toothpaste/water mixture. Increasing TU-filler in the composite resulted in as much as a 78% reduction in stress, coupled with an increase in fracture toughness. Conversion was similar for all groups. After simulated tooth brushing, gloss reduction was lower for TU-containing composites and surface roughness was less than or equal to the control.

The psychological impact of Stevens-Johnson syndrome and toxic epidermal necrolysis on patients' lives: a Critically Appraised Topic.

CLINICAL SCENARIO: A 65-year-old man presented with a 12-h history of deteriorating rash. Two weeks previously he had completed a course of neoadjuvant chemotherapy for ductal carcinoma of the breast. On examination there were bullae, widespread atypical targetoid lesions and 15% epidermal detachment. There was no mucosal involvement on presentation, but subsequently it did evolve. Skin biopsy showed subepidermal blistering with epidermal necrosis. This confirmed our clinical diagnosis of overlap Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). On transfer to intensive care he was anxious and fearful. MANAGEMENT QUESTION: What are the psychological impacts of SJS/TEN on this man's life? BACKGROUND: SJS and TEN have devastating outcomes for those affected. OBJECTIVES: To conduct a Critically Appraised Topic to (i) analyse existing research related to the psychological impact of SJS and TEN and (ii) apply the results to the clinical scenario. METHODS: Seven electronic databases were searched for publications focusing on the psychological impact of SJS/TEN on adults over 18 years of age. RESULTS: Six studies met the inclusion criteria. Healthcare practitioners' (HCPs') lack of information around the disorder was highlighted. Patients experienced undue stress and fear. Some patients had symptoms aligned to post-traumatic stress disorder (PTSD), anxiety and depression. DISCUSSION AND RECOMMENDATION: The evidence suggests that SJS and TEN impact psychologically on patients' lives. Education of HCPs, to address their lack of awareness and information on SJS/TEN, should facilitate their capacity to provide information and support to patients, thereby reducing patient anxiety. On discharge, a follow-up appointment with relevant HCPs to reduce the possibility of PTSD occurring should be considered.

Perineural Invasion in Head and Neck Cancer.

Perineural invasion (PNI) is a mechanism of tumor dissemination that can provide a challenge to tumor eradication and that is correlated with poor survival. Squamous cell carcinoma, the most common type of head and neck cancer, has a high prevalence of PNI. This review provides an overview of clinical studies on the outcomes and factors associated with PNI in head and neck cancer and on findings on cancer-nerve crosstalk.

Subcortical volumetric abnormalities in bipolar disorder.

Considerable uncertainty exists about the defining brain changes associated with bipolar disorder (BD). Understanding and quantifying the sources of uncertainty can help generate novel clinical hypotheses about etiology and assist in the development of biomarkers for indexing disease progression and prognosis. Here we were interested in quantifying case-control differences in intracranial volume (ICV) and each of eight subcortical brain measures: nucleus accumbens, amygdala, caudate, hippocampus, globus pallidus, putamen, thalamus, lateral ventricles. In a large study of 1710 BD patients and 2594 healthy controls, we found consistent volumetric reductions in BD patients for mean hippocampus (Cohen's d=-0.232; P=3.50 × 10-7) and thalamus (d=-0.148; P=4.27 × 10-3) and enlarged lateral ventricles (d=-0.260; P=3.93 × 10-5) in patients. No significant effect of age at illness onset was detected. Stratifying patients based on clinical subtype (BD type I or type II) revealed that BDI patients had significantly larger lateral ventricles and smaller hippocampus and amygdala than controls. However, when comparing BDI and BDII patients directly, we did not detect any significant differences in brain volume. This likely represents similar etiology between BD subtype classifications. Exploratory analyses revealed significantly larger thalamic volumes in patients taking lithium compared with patients not taking lithium. We detected no significant differences between BDII patients and controls in the largest such comparison to date. Findings in this study should be interpreted with caution and with careful consideration of the limitations inherent to meta-analyzed neuroimaging comparisons.

A novel approach to biomarker discovery in head and neck cancer using an autoantibody signature.

Despite the dismal prognosis for patients with squamous cell carcinoma of the head and neck (SCCHN), there have been no novel treatments in over 40 years. Identification of novel tumor antigens in SCCHN will facilitate the identification of potential novel treatment targets. Tumor antigens are proteins selectively expressed by tumor cells and recognized by the host immune system. Phage-displayed tumor antigens were enriched by biopanning with normal and then SCCHN-specific serum. Ninety-six phage clones were sequenced for identification, and 21 clones were validated using Luminex. One of these proteins, L23, a novel tumor antigen in SCCHN, was validated as an oncogene. L23 is upregulated in SCCHN compared with normal keratinocytes. Knockdown of L23 inhibited proliferation, invasion and cell survival. Overexpression of L23 had the reverse effect. Overexpression of L23 in non malignant cells led to transformation. Injection of SCCHN cells with knockdown of L23 in mice, induced tumors that were significantly smaller than control tumors. In conclusion, the immunomic screen yielded a panel of antigens specific to SCCHN; one of these proteins, L23, is a novel oncogene in SCCHN.

Biomarkers of epithelial-mesenchymal transition in squamous cell carcinoma.

An understanding of the process by which tumor cells destroy the basement membrane of the surface epithelium, invade, and metastasize is essential to the development of novel treatment of head and neck squamous cell carcinoma (HNSCC). In recent years, there has been increased interest in the role of epithelial-mesenchymal transition (EMT) in invasion. EMT is a process that describes the development of motile, mesenchymal-like cells from non-motile parent epithelial cells. There are 3 known types of EMT that mediate development, wound healing, and carcinogenesis. This review summarizes studies of known EMT biomarkers in the context of HNSCC progression. The biomarkers discussed come from a wide range of proteins, including cell-surface proteins (E-cadherin, N-cadherin, and Integrins), cytoskeletal proteins (α-Smooth Muscle Actin, Vimentin, and ß-catenin), extracellular matrix proteins (Collagens, Fibronectin, and Laminin), and transcription factors (SNAIL1, SNAIL2, TWIST, and LEF-1). Overall, the findings of these studies suggest that EMT mediates HNSCC progression. The mechanistic role of the EMT markers that have been associated with HNSCC should be more clearly defined if new anti-HNSCC therapies to block EMT progression are to be developed.

Impact of methodologic choice for automatic detection of different aspects of brain atrophy by using temporal lobe epilepsy as a model.

BACKGROUND AND PURPOSE: VBM, DBM, and cortical thickness measurement techniques are commonly used automated methods to detect structural brain changes based on MR imaging. The goal of this study was to demonstrate the pathology detected by the 3 methods and to provide guidance as to which method to choose for specific research questions. This goal was accomplished by 1) identifying structural abnormalities associated with TLE with (TLE-mts) and without (TLE-no) hippocampal sclerosis, which are known to be associated with different types of brain atrophy, by using these 3 methods; and 2) determining the aspect of the disease pathology identified by each method. MATERIALS AND METHODS: T1-weighted MR images were acquired for 15 TLE-mts patients, 14 TLE-no patients, and 33 controls on a high-field 4T scanner. Optimized VBM was carried out by using SPM software, DBM was performed by using a fluid-flow registration algorithm, and cortical thickness was analyzed by using FS-CT. RESULTS: In TLE-mts, the most pronounced volume losses were identified in the ipsilateral hippocampus and mesial temporal region, bilateral thalamus, and cerebellum, by using SPM-VBM and DBM. In TLE-no, the most widespread changes were cortical and identified by using FS-CT, affecting the bilateral temporal lobes, insula, and frontal and occipital lobes. DBM revealed 2 clusters of reduced volume complementing FS-CT analysis. SPM-VBM did not show any significant volume losses in TLE-no. CONCLUSIONS: These results demonstrate that the 3 methods detect different aspects of brain atrophy and that the choice of the method should be guided by the suspected pathology of the disease.

The tumor suppressor gene rap1GAP is silenced by miR-101-mediated EZH2 overexpression in invasive squamous cell carcinoma.

Rap1GAP is a critical tumor suppressor gene that is downregulated in multiple aggressive cancers, such as head and neck squamous cell carcinoma, melanoma and pancreatic cancer. However, the mechanistic basis of rap1GAP downregulation in cancers is poorly understood. By employing an integrative approach, we demonstrate polycomb-mediated repression of rap1GAP that involves Enhancer of Zeste Homolog 2 (EZH2), a histone methyltransferase in head and neck cancers. We further demonstrate that the loss of miR-101 expression correlates with EZH2 upregulation, and the concomitant downregulation of rap1GAP in head and neck cancers. EZH2 represses rap1GAP by facilitating the trimethylation of histone 3 at lysine 27, a mark of gene repression, and also hypermethylation of rap1GAP promoter. These results provide a conceptual framework involving a microRNA-oncogene-tumor suppressor axis to understand head and neck cancer progression.

End-of-life issues in intensive care units: a national random survey of nurses' knowledge and beliefs.

OBJECTIVE: To investigate the knowledge, beliefs, and ethical concerns of nurses caring for patients dying in intensive care units. METHODS: A survey was mailed to 3000 members of the American Association of Critical-Care Nurses. The survey contained various scenarios depicting end-of-life actions for patients: pain management, withholding or withdrawing life support, assisted suicide, and voluntary and nonvoluntary euthanasia. RESULTS: Most of the respondents (N = 906) correctly identified the distinctions among the end-of-life actions depicted in the scenarios. Almost all (99%-100%) agreed with the actions of pain management and withholding or withdrawing life support. A total of 83% disagreed with assisted suicide, 95% disagreed with voluntary euthanasia, and 89% to 98% disagreed with nonvoluntary euthanasia. Most (78%) thought that dying patients frequently (31%) or sometimes (47%) received inadequate pain medicine, and almost all agreed with the double-effect principle. Communication between nurses and physicians was generally effective, but unit-level conferences that focused on grief counseling and debriefing staff rarely (38%) or never (49%) occurred. Among the respondents, 37% had been asked to assist in hastening a patient's death. Although 59% reported that they seldom acted against their consciences in caring for dying patients, 34% indicated that they sometimes had acted against their conscience, and 6% had done so to a great extent. CONCLUSIONS: Intensive care unit nurses strongly support good pain management for dying patients and withholding or withdrawing life-sustaining therapies to allow unavoidable death. The vast majority oppose assisted suicide and euthanasia. Wider professional and public dialogue on end-of-life care in intensive care units is warranted.

A two-platform task reveals a deficit in the ability of rats to return to the start location in the water maze.

The ability of rats to return to the start location was examined with a 4-arm radial water maze. The task required rats to find 2 hidden platforms in sequence. Rats were released from 1 of 3 arms and there was a platform located in the fourth arm. Once a rat found this platform, a 2nd platform was raised in another location, which was either the start location, for 1 group, or another fixed location, for a control group. Across 3 experiments, all rats learned the location of the 1st fixed platform in 80 to 120 trials. However, rats had difficulty finding a 2nd platform if it was at the start location. Control groups revealed that rats could learn 2 platform locations and that the difficulty in learning to return to the start location did not seem to be attributable to its aversive nature. In separate groups, exposure to the start location was increased by starting the rats from an initially stable platform. Rats still did not readily learn to return to the start location. The authors suggest that start location, when varied, cannot readily be used to define the location of a hidden platform.

Subcellular localization of a high affinity binding site for D-myo-inositol 1,4,5-trisphosphate from Chenopodium rubrum.

It is now generally accepted that a phosphoinositide cycle is involved in the transduction of a variety of signals in plant cells. In animal cells, the binding of D-myo-inositol 1,4,5-trisphosphate (InsP(3)) to a receptor located on the endoplasmic reticulum (ER) triggers an efflux of calcium release from the ER. Sites that bind InsP(3) with high affinity and specificity have also been described in plant cells, but their precise intracellular locations have not been conclusively identified. In contrast to animal cells, it has been suggested that in plants the vacuole is the major intracellular store of calcium involved in signal induced calcium release. The aim of this work was to determine the intracellular localization of InsP(3)-binding sites obtained from 3-week-old Chenopodium rubrum leaves. Microsomal membranes were fractionated by sucrose density gradient centrifugation in the presence and absence of Mg(2+) and alternatively by free-flow electrophoresis. An ER-enriched fraction was also prepared. The following enzymes were employed as specific membrane markers: antimycin A-insensitive NADH-cytochrome c reductase for ER, cytochrome c oxidase for mitochondrial membrane, pyrophosphatase for tonoplast, and 1,3-beta-D-glucansynthase for plasma membrane. In all membrane separations, InsP(3)-binding sites were concentrated in the fractions that were enriched with ER membranes. These data clearly demonstrate that the previously characterized InsP(3)-binding site from C. rubrum is localized on the ER. This finding supports previous suggestions of an alternative non-vacuolar InsP(3)-sensitive calcium store in plant cells.

A professional code of ethics provides guidance for genetic nursing practice.

While ethical quandaries and dilemmas are commonplace for nurses, recent advances in human genetics have and will continue to create new challenges and controversies. Throughout time, nursing has been an ethical endeavour, with nurses viewing the ethical mandates of their responsibilities on a par with other core dimensions of their professional life. The (American) profession's code of ethics, Code for nurses with interpretive statements, provides direction for practice and for the fulfillment of ethical obligations. The explication of these ethical norms and values that shape professional practice is necessary as nurses confront the integration of genetic services into health care. The goal of preserving professional integrity and ethical soundness in the context of genetic health care mandates that nurses rely on and act upon the profession's national and international codes of ethics.

Assisted suicide: how nurses should respond.

However compassionate the motives behind assisted suicide initiatives, the risks and harm for patients, health professionals and the public are too great. The moral and professional challenge should not revolve around assisted suicide but be directed at reversing the dying person's despair and fulfilling the obligation to provide competent and committed care to the dying.

Unraveling ethical issues in palliative care.

OBJECTIVES: To describe the ethical issues inherent in palliative care and the essential role of nurses in addressing the ethical dimensions of professional practice. DATA SOURCE: Review articles, research studies, and books related to ethical issues in palliative care. CONCLUSIONS: Nurses in all roles and practice settings confront numerous ethical concerns. Some of the most perplexing and troubling ethical issues arise within the context of palliative care. Being prepared to deal with these ethical issues can foster patient and family well-being and protect the integrity of the nurse. IMPLICATIONS FOR NURSING PRACTICE: Oncology nurses have a vital role in improving the quality of end-of-life care. Attention to the ethical dimension of palliative care is necessary to accomplishing this.

A road map for navigating end-of-life care.

As nurses begin to develop the sensitivities and skills necessary to preserve the integrity of clinical care and professional life, they must recognize the legitimacy of their perspectives and the value and consequences they have for the well-being of patient and family care. Nurses have much to contribute to the development of ethical practice environments for patients, families, multidisciplinary team members, and themselves. The frenzied, and at times anesthetized, culture of clinical settings can mitigate against the kind of deliberate reflection that is necessary if nurses are to act with ethical integrity. Knowing the rules of the road for end-of-life care and being attentive to common warning signs and addressing them proactively, enables nurses to provide patients and families with the highest quality care at the end of life.

Learning from practice? Mental health nurses' perceptions and experiences of clinical supervision.

In recent years nursing as a whole has moved from a position of apparently little manifest concern in the issue of 'clinical supervision' to a veritable explosion of interest which is beginning to find expression in the literature. Beginning with a discussion of clinical supervision from within a psychodynamically informed interpersonal nursing framework this paper reports on a small scale qualitative inquiry which aimed to explore mental health nurses' perceptions and experiences of clinical supervision. Analysis of data derived from a series of semi-structured interviews provides very encouraging early indications that mental health nurses are becoming better able to reflect upon the nature of their own formative learning needs and so to take seriously their need for professional support as they strive towards a more therapeutic relationship with their patients. However, whilst all of the participants in the study had a positive perception of the potential value of clinical supervision, there is clear evidence to suggest that their actual experience was that 'good enough supervision' was more the exception than the rule. The participants' perceptions and experiences are described and the implications for research, practice, education and the management of service delivery systems are outlined.