Cluster-surface and cluster-cluster interactions: Ab initio calculations and modeling of van der Waals forces

We present fully ab-initio calculations of van der Waals coefficients for two different situations: i) the interaction between hydrogenated silicon clusters; and ii) the interactions between these nanostructures and a non metallic surface (a silicon or a silicon carbide surface). The methods used are very efficient, and allow the calculation of systems containing hundreds of atoms. The results obtained are further analyzed and understood with the help of simple models. These models can be of interest for molecular dynamics simulations of silicon nanostructures on surfaces, where they can give a very fast yet sufficiently accurate determination of the van der Waals interaction at large separations.Comment: Phys. Rev.

The Role of Appearance in Adolescents’ Experiences of Neurofibromatosis Type 1: A Survey of Young People and Parents

© 2016, National Society of Genetic Counselors, Inc. Neurofibromatosis type 1 (NF1) is a genetic condition which can result in varying degrees of visible difference (disfigurement). Adolescence is a time when appearance concerns become more salient for many young people and is acknowledged as a particularly challenging time for individuals with NF1. There is currently little research into the psychosocial impact of the appearance changes associated with NF1 during this stage of life. In order to address this, surveys of young people with NF1 aged 14–24years (n=73), and parents of young people with NF1 (n=55) were developed following interview studies with these groups. The surveys included the Perceived Stigma Questionnaire, Social Comfort Questionnaire, Body Esteem Scale (appearance subscale) and the Subjective Happiness Scale. Young people and parents identified appearance as central to young peoples’ experience of NF1, however no significant difference was found on measures of body esteem, happiness, stigma or social comfort between those young people who reported their NF1 was noticeable to others and those who reported it was not. Findings from the parent survey indicated that their reports of greater perceived noticeability did relate to greater perceived stigma and lower levels of social comfort. Findings highlight the importance of attending to young people’s concerns around appearance in general and managing the possibility of future appearance changes, rather than the current noticeability of NF1

Breast cancer in neurofibromatosis 1: survival and risk of contralateral breast cancer in a five country cohort study

PurposeNeurofibromatosis 1 (NF1) is an autosomal dominant condition caused by pathogenic variants of the NF1 gene. A markedly increased risk of breast cancer is associated with NF1. We have determined the breast cancer survival and risk of contralateral breast cancer in NF1.MethodsWe included 142 women with NF1 and breast cancer from five cohorts in Europe and 335 women without NF1 screened for other familial breast cancers. Risk of contralateral breast cancer and death were assessed by Kaplan–Meier analysis with delayed entry.ResultsOne hundred forty-two women with NF1 were diagnosed for breast cancer at a median age of 46.9 years (range 27.0–84.3 years) and then followed up for 1235 person-years (mean = 8.70 years). Twelve women had contralateral breast cancer with a rate of 10.5 per 1000 years. Cumulative risk for contralateral breast cancer was 26.5% in 20 years. Five and 10-year all-cause survival was 64.9% (95% confidence interval [CI] = 54.8–76.8) and 49.8% (95%CI = 39.3–63.0). Breast cancer–specific 10-year survival was 64.2% (95% CI = 53.5–77.0%) compared with 91.2% (95% CI = 87.3–95.2%) in the non-NF1 age-matched population at increased risk of breast cancer.ConclusionWomen with NF1 have a substantial contralateral breast cancer incidence and poor survival. Early start of breast cancer screening may be a way to improve the survival.</p

Descriptive epidemiology of stigma against depression in a general population sample in Alberta

<p>Abstract</p> <p>Background</p> <p>Mental health illnesses, such as depression, are responsible for a growing disease burden worldwide. Unfortunately, effective treatment is often impeded by stigmatizing attitudes of other individuals, which have been found to lead to a number of negative consequences including reduced help-seeking behavior and increased social distance. Despite the high prevalence of depression in Canada, little research has been conducted to examine stigma against depression in the Canadian general population. Such information is crucial to understanding the current state of stigmatizing attitudes in the Canadian communities, and framing future stigma reduction initiatives. The objectives of this study were to estimate the percentages of various stigmatizing attitudes toward depression in a general population sample and to compare the percentages by demographics and socioeconomic characteristics.</p> <p>Methods</p> <p>We conducted a cross-sectional telephone survey in Alberta, Canada, between February and June 2006. Random digit dialing was used to recruit participants who were aged 18-74 years old (n = 3047). Participants were presented a case vignette describing a depressed individual, and responded to a 9-item Personal Stigma questionnaire. The percentages of stigmatizing attitudes were estimated and compared by demographic and socioeconomic variables.</p> <p>Results</p> <p>Among the participants, 45.9% endorsed that depressed individuals were unpredictable and 21.9% held the view that people with depression were dangerous. Significant differences in stigmatizing attitudes were found by gender, age, education, and immigration status. A greater proportion of men than women held stigmatizing views on each stigma item. No consistent trend emerged by age in stigma against depression. Participants with higher levels of education reported less stigmatizing attitudes than those with less education. Participants who were not born in Canada were more likely to hold stigmatizing attitudes than those who were born in Canada.</p> <p>Conclusion</p> <p>In the general population, stigmatizing attitudes towards depression differ by demographic characteristics. Men, those with less education and immigrants should be the targets of stigma reduction campaigns.</p

Parents’ experiences of caring for a young person with neurofibromatosis type 1 (NF1): a qualitative study

Neurofibromatosis type 1 (NF1) is a variable and unpredictable genetic condition that can lead to changes to an individual’s appearance. Research has started to explore children’s and young people’s experiences of living with the condition; however, there is a lack of research with parents. This exploratory qualitative study set out to examine parents’ experiences of caring for a young person with NF1. Seven parents took part in semi structured interviews which were subjected to a thematic analysis. Three key themes were identified which related to managing the uncertainty of the condition, the impact of an altered appearance, and others’ awareness and understanding of NF1. Parents felt that understanding NF1 themselves in order to support their child was beneficial whilst a perceived lack of understanding by others was cited as a significant challenge. Parents require trustworthy information and also more widely call for greater understanding and awareness of the condition

Distribution pattern of psoriasis, anxiety and depression as possible causes of sexual dysfunction in patients with moderate to severe psoriasis

BACKGROUND: Psoriasis may significantly impair sexual function. Depression and organic factors appear to play a key role in this relation. However, beyond genital psoriasis, the importance of the disease's distribution patterns has not been considered. OBJECTIVES: To research sexual function in psoriasis patients and investigate the roles of anxiety, depression and psoriasis' distribution patterns in sexual dysfunction. METHODS: A comparative study matched for sex and age was performed. Eighty patients with moderate to severe psoriasis and 80 healthy controls were included. The participants completed the Massachusetts General Hospital-Sexual Functioning Questionnaire, the Hospital Anxiety and Depression Scale, and the Self-Administered Psoriasis Area and Severity Index. RESULTS: Psoriasis was associated with sexual dysfunction, odds ratio=5.5 (CI 95% 2.6-11.3; p<0.001). Certain distribution patterns of psoriasis, involving specific body regions, were associated with an increase in sexual dysfunction in the group presenting the disease, odds ratio 7.9 (CI 95% 2.3-33.4; p<0.001). Multivariate logistic regression analysis identified anxiety and depression, and the involvement of these specific areas, as possible independent risk factors for sexual dysfunction in patients with moderate to severe psoriasis. CONCLUSION: This study identifies body areas potentially related to sexual dysfunction, independently of anxiety and depression, in psoriasis patients. The results suggest that the assessment of sexual dysfunction and the involvement of these body areas should be considered as disease severity criteria when choosing the treatment for psoriasis patients

Tracking the impact of depression in a perspective-taking task

Research has identified impairments in Theory of Mind (ToM) abilities in depressed patients, particularly in relation to tasks involving empathetic responses and belief reasoning. We aimed to build on this research by exploring the relationship between depressed mood and cognitive ToM, specifically visual perspective-taking ability. High and low depressed participants were eye-tracked as they completed a perspective-taking task, in which they followed the instructions of a ‘director’ to move target objects (e.g. a “teapot with spots on”) around a grid, in the presence of a temporarily-ambiguous competitor object (e.g. a “teapot with stars on”). Importantly, some of the objects in the grid were occluded from the director’s (but not the participant’s) view. Results revealed no group-based difference in participants’ ability to use perspective cues to identify the target object. All participants were faster to select the target object when the competitor was only available to the participant, compared to when the competitor was mutually available to the participant and director. Eye-tracking measures supported this pattern, revealing that perspective directed participants’ visual search immediately upon hearing the ambiguous object’s name (e.g. “teapot”). We discuss how these results fit with previous studies that have shown a negative relationship between depression and ToM

Cutaneous neurofibromas Current clinical and pathologic issues

ObjectiveTo present the current terminology and natural history of neurofibromatosis 1 (NF1) cutaneous neurofibromas (cNF).MethodsNF1 experts from various research and clinical backgrounds reviewed the terms currently in use for cNF as well as the clinical, histologic, and radiographic features of these tumors using published and unpublished data.ResultsNeurofibromas develop within nerves, soft tissue, and skin. The primary distinction between cNF and other neurofibromas is that cNF are limited to the skin whereas other neurofibromas may involve the skin, but are not limited to the skin. There are important cellular, molecular, histologic, and clinical features of cNF. Each of these factors is discussed in consideration of a clinicopathologic framework for cNF.ConclusionThe development of effective therapies for cNF requires formulation of diagnostic criteria that encompass the clinical and histologic features of these tumors. However, there are several areas of overlap between cNF and other neurofibromas that make distinctions between cutaneous and other neurofibromas more difficult, requiring careful deliberation with input across the multiple disciplines that encounter these tumors and ultimately, prospective validation. The ultimate goal of this work is to facilitate accurate diagnosis and meaningful therapeutics for cNF

Supportive care in the acute phase of Stevens-Johnson syndrome and toxic epidermal necrolysis : an international, multidisciplinary Delphi-based consensus

Background Supportive care is the cornerstone of management of adult and paediatric Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). However, consensus on the modalities of supportive care is lacking. Objectives Our aim in this international multicentric Delphi exercise was to establish a multidisciplinary expert consensus to standardize recommendations regarding supportive care in the acute phase of SJS/TEN. Methods Participants were sent a survey via the online tool SurveyMonkey, consisting of 103 statements organized into 11 topics: multidisciplinary team composition, suspect drug management, infection prevention, fluid resuscitation and prevention of hypothermia, nutritional support, pain and psychological distress management, management of acute respiratory failure, local skincare, ophthalmological management, management of other mucosa, and additional measures. Participants evaluated the level of appropriateness of each statement on a scale of 1 (extremely inappropriate) to 9 (extremely appropriate). The results were analysed according to the RAND/UCLA Appropriateness Method. Results Forty-five participants from 13 countries (on three continents) participated. After the first round, a consensus was obtained for 82.5% of the 103 initially proposed statements. After the second round, a final consensus was obtained for 102 statements. Conclusions We have reached an international Delphi-based consensus on best supportive care practice for SJS/TEN. Our expert consensus should help guide physicians in treating patients with SJS/TEN and thereby improve short-term prognosis and the risk of sequelae.Peer reviewe

Toxic epidermal necrolysis and Stevens-Johnson syndrome

Toxic epidermal necrolysis (TEN) and Stevens Johnson Syndrome (SJS) are severe adverse cutaneous drug reactions that predominantly involve the skin and mucous membranes. Both are rare, with TEN and SJS affecting approximately 1or 2/1,000,000 annually, and are considered medical emergencies as they are potentially fatal. They are characterized by mucocutaneous tenderness and typically hemorrhagic erosions, erythema and more or less severe epidermal detachment presenting as blisters and areas of denuded skin. Currently, TEN and SJS are considered to be two ends of a spectrum of severe epidermolytic adverse cutaneous drug reactions, differing only by their extent of skin detachment. Drugs are assumed or identified as the main cause of SJS/TEN in most cases, but Mycoplasma pneumoniae and Herpes simplex virus infections are well documented causes alongside rare cases in which the aetiology remains unknown. Several drugs are at "high" risk of inducing TEN/SJS including: Allopurinol, Trimethoprim-sulfamethoxazole and other sulfonamide-antibiotics, aminopenicillins, cephalosporins, quinolones, carbamazepine, phenytoin, phenobarbital and NSAID's of the oxicam-type. Genetic susceptibility to SJS and TEN is likely as exemplified by the strong association observed in Han Chinese between a genetic marker, the human leukocyte antigen HLA-B*1502, and SJS induced by carbamazepine. Diagnosis relies mainly on clinical signs together with the histological analysis of a skin biopsy showing typical full-thickness epidermal necrolysis due to extensive keratinocyte apoptosis. Differential diagnosis includes linear IgA dermatosis and paraneoplastic pemphigus, pemphigus vulgaris and bullous pemphigoid, acute generalized exanthematous pustulosis (AGEP), disseminated fixed bullous drug eruption and staphyloccocal scalded skin syndrome (SSSS). Due to the high risk of mortality, management of patients with SJS/TEN requires rapid diagnosis, evaluation of the prognosis using SCORTEN, identification and interruption of the culprit drug, specialized supportive care ideally in an intensive care unit, and consideration of immunomodulating agents such as high-dose intravenous immunoglobulin therapy. SJS and TEN are severe and life-threatening. The average reported mortality rate of SJS is 1-5%, and of TEN is 25-35%; it can be even higher in elderly patients and those with a large surface area of epidermal detachment. More than 50% of patients surviving TEN suffer from long-term sequelae of the disease