Methylating mushrooms

Peptide N-methylation is an important strategy used by medicinal chemists to improve cell permeability, oral bioavailability, and target affinity of peptide-based inhibitors. Correspondingly, N-methyl amides appear extensively in bioactive natural products. In the case of the immunosuppressant cyclosporine, for example, specific N-methylation of seven out of ten backbone amide nitrogens in the cyclic decapeptide is thought to allow a conformational ‘shapeshifting’ that hides polar N–H moieties and facilitates passive diffusion across cell membranes. Until now, N-methylation has primarily been the mark of peptide natural products from complex nonribosomal peptide synthetase (NRPS) assembly lines, and has not previously been found among their cousins, the ribosomally synthesized and post-translationally modified peptide (RiPP) natural products. In this issue, van der Velden et al. uncover the biosynthetic origins of the omphalotins, peptide natural products from the bioluminescent fungus O. olearius (Fig. 1a), and bring peptide backbone N-methylation into the realm of peptide post-translational modifications

Selective attrition and bias in a longitudinal health survey among survivors of a disaster

BACKGROUND: Little is known about the response mechanisms among survivors of disasters. We studied the selective attrition and possible bias in a longitudinal study among survivors of a fireworks disaster. METHODS: Survivors completed a questionnaire three weeks (wave 1), 18 months (wave 2) and four years post-disaster (wave 3). Demographic characteristics, disaster-related factors and health problems at wave 1 were compared between respondents and non-respondents at the follow-up surveys. Possible bias as a result of selective response was examined by comparing prevalence estimates resulting from multiple imputation and from complete case analysis. Analysis were stratified according to ethnic background (native Dutch and immigrant survivors). RESULTS: Among both native Dutch and immigrant survivors, female survivors and survivors in the age categories 25–44 and 45–64 years old were more likely to respond to the follow-up surveys. In general, disasters exposure did not differ between respondents and non-respondents at follow-up. Response at follow-up differed between native Dutch and non-western immigrant survivors. For example, native Dutch who responded only to wave 1 reported more depressive feelings at wave 1 (59.7%; 95% CI 51.2–68.2) than Dutch survivors who responded to all three waves (45.4%; 95% CI 41.6–49.2, p < 0.05). Immigrants who responded only to wave 1 had fewer health problems three weeks post-disaster such as depressive feelings (M = 69.3%; 95% CI 60.9–77.6) and intrusions and avoidance reactions (82.7%; 95% CI 75.8–89.5) than immigrants who responded to all three waves (respectively 89.9%; 95% CI 83.4–96.9 and 96.3%; 95% CI 92.3–100, p < .01). Among Dutch survivors, the imputed prevalence estimates of wave 3 health problems tended to be higher than the complete case estimates. The imputed prevalence estimates of wave 3 health problems among immigrants were either unaffected or somewhat lower than the complete case estimates. CONCLUSION: Our results indicate that despite selective response, the complete case prevalence estimates were only somewhat biased. Future studies, both among survivors of disasters and among the general population, should not only examine selective response, but should also investigate whether selective response has biased the complete case prevalence estimates of health problems by using statistical techniques such as multiple imputation

Use of mental health services among disaster survivors: predisposing factors

<p>Abstract</p> <p>Background</p> <p>Given the high prevalence of mental health problems after disasters it is important to study health services utilization. This study examines predictors for mental health services (MHS) utilization among survivors of a man-made disaster in the Netherlands (May 2000).</p> <p>Methods</p> <p>Electronic records of survivors (n = 339; over 18 years and older) registered in a mental health service (MHS) were linked with general practice based electronic medical records (EMRs) of survivors and data obtained in surveys. EMR data were available from 16 months pre-disaster until 3 years post-disaster. Symptoms and diagnoses in the EMRs were coded according to the International Classification of Primary Care (ICPC). Surveys were carried out 2–3 weeks and 18 months post-disaster, and included validated questionnaires on psychological distress, post-traumatic stress reactions and social functioning. Demographic and disaster-related variables were available. Predisposing factors for MHS utilization 0–18 months and 18–36 months post-disaster were examined using multiple logistic regression models.</p> <p>Results</p> <p>In multiple logistic models, adjusting for demographic and disaster related variables, MHS utilization was predicted by demographic variables (young age, immigrant, public health insurance, unemployment), disaster-related exposure (relocation and injuries), self-reported psychological problems and pre- and post-disaster physician diagnosed health problems (chronic diseases, musculoskeletal problems). After controlling for all health variables, disaster intrusions and avoidance reactions (OR:2.86; CI:1.48–5.53), hostility (OR:2.04; CI:1.28–3.25), pre-disaster chronic diseases (OR:1.82; CI:1.25–2.65), injuries as a result of the disaster (OR:1.80;CI:1.13–2.86), social functioning problems (OR:1.61;CI:1.05–2.44) and younger age (OR:0.98;CI:0.96–0.99) predicted MHS utilization within 18 months post-disaster. Furthermore, disaster intrusions and avoidance reactions (OR:2.29;CI:1.04–5.07) and hostility (OR:3.77;CI:1.51–9.40) predicted MHS utilization following 18 months post-disaster.</p> <p>Conclusion</p> <p>This study showed that several demographic and disaster-related variables and self-reported and physician diagnosed health problems predicted post-disaster MHS-use. The most important factors to predict post-disaster MHS utilization were disaster intrusions and avoidance reactions and symptoms of hostility (which can be identified as symptoms of PTSD) and pre-disaster chronic diseases.</p

The casualty chain inventory: a new scale for measuring peritraumatic responses: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Peritraumatic psychological- and sensory impressions in victims of civilian accidents are only partly understood. This study scrutinizes the level and duration of perceived psychological threat at <it>scene of injury </it>as well as <it>in hospital </it>(the casualty chain) measured by the Casualty Chain Inventory (CCI). The purpose of the study was to assess and validate the CCI, and to examine the correlations between the new instrument and stress responses measured by the Impact of Event Scale (IES) and the Post-traumatic Stress Scale-10 (PTSS-10)</p> <p>Methods</p> <p>Three hundred and fifteen injured, conscious, hospitalised patients were assessed with a self-report questionnaire. The CCI consists of eight items including sensory impressions and well-known psychological responses to trauma.</p> <p>Results</p> <p>The internal consistency of the CCI was solid (Cronbach's alpha: .83-.85). A factor analysis revealed two components, "perception" and "dissociation". The instrument correlates significantly with the Impact of Event Scale (r = 0.47 - 0.54) and the Posttraumatic Stress Scale-10 (r = 0.32 - 0.50). The explained variance is high both at the scene of injury (61%) and in the hospital (65%). Dissociation and perception either used as a two-factor solution or as a sum score measured in the hospital, gave the strongest prediction for later psychological distress.</p> <p>Conclusions</p> <p>The CCI appears to be a useful screening instrument for, at an early state, identifying patients hospitalized after a physical incident at risk for subsequent psychological distress.</p

Non-adherence to antimicrobial treatment guidelines results in more broad-spectrum but not more appropriate therapy

Mortality in patients admitted with sepsis is high and the increasing incidence of infections with multiresistant bacteria is a worldwide problem. Many hospitals have local antimicrobial guidelines to assure effective treatment and limit the use of broad-spectrum antibiotics, thereby reducing the selection of resistant bacteria. We evaluated adherence to the antimicrobial treatment guidelines of our hospital in patients presenting to the emergency department (ED) with sepsis and assessed the in vitro susceptibility of isolated pathogens to the guideline-recommended treatment and the prescribed treatment. We included all adult patients with a known or suspected infection and two or more extended systemic inflammatory response syndrome (SIRS) criteria. Patients who did not receive antimicrobial treatment, presented with infections not included in the guidelines, or had more than one possible focus of infection were excluded. A total of 276 ED visits (262 patients) were included. Guideline-concordant treatment was prescribed in 168 visits (61%). In the case of guideline-disconcordant treatment, 87% was more broad-spectrum than guideline-recommended treatment. A microbiological diagnosis was established in 96 visits (35%). The susceptibility of the pathogens isolated from patients treated with guideline-concordant treatment (n = 68) and guideline-disconcordant treatment (n = 28) to guideline-recommended treatment (91% versus 89%) and to prescribed treatment (91% versus 93%) was similar (p = 0.77 and p = 0.79, respectively). In conclusion, non-adherence to the guidelines occurred frequently and resulted in more broad-spectrum empirical therapy. This did not result in a higher rate of susceptibility of the isolated pathogens to the prescribed empirical therapy

Lonely but avoidant—the unfortunate juxtaposition of loneliness and self-disgust

Loneliness is prevalent worldwide and is a known risk factor for numerous physical and mental health outcomes. The health consequences of chronic loneliness coupled with the cost on public health care has necessitated the development of interventions and campaigns to end loneliness globally. According to a recent meta-analysis, such interventions focus on improving social skills, increasing opportunities for social contact/support (i.e., reducing social isolation) or addressing maladaptive cognition (e.g., irrational thoughts, self-defeating, and self-blame thoughts). The results showed that changing maladaptive thoughts offer “the best chance” for alleviating feelings of loneliness. In accordance with the latter approach, this paper proposes a new paradigm in understanding and treating loneliness that takes into account self-disgust, an aversive self-conscious affective state that reflects disgust directed towards the self. Based on findings from published and unpublished data, it is argued that interventions against loneliness that focus exclusively on improving social skills and increasing opportunities for social contact may be ineffective because lonelier people experience more self-disgust, which makes them more socially inhibited and reluctant to connect with other people. Future interventions should consider self-disgust in the treatment of loneliness and explore ways to counter feelings of self-disgust

Cytokeratin 8/18 expression indicates a poor prognosis in squamous cell carcinomas of the oral cavity

BACKGROUND: Intermediary filaments are involved in cell motility and cancer progression. In a variety of organs, the expression of distinct intermediary filaments are associated with patient prognosis. In this study, we seeked to define the prognostic potential of cytokeratin and vimentin expression patterns in squamous cell carcinomas (SCC's) of the oral cavity. METHODS: 308 patients with histologically proven and surgically treated squamous cell carcinomas of the oral cavity were investigated for the immunohistochemical expression of a variety of intermediary filaments including high- and low-molecular weight cytokeratins (Ck's), such as Ck 5/6, Ck 8/18, Ck 1, CK 10, Ck 14, Ck 19 and vimentin, using the tissue microarray technique. Correlations between clinical features and the expression of Cytokeratins and vimentin were evaluated statistically by Kaplan-Meier curves and multivariate Cox regression analysis. RESULTS: The expression of Ck 8/18 and Ck 19 were overall significantly correlated with a poor clinical prognosis (Ck 8/18 p = 0.04; Ck19 p < 0.01). These findings could also be reproduced for Ck 8/18 in primary nodal-negative SCC's and held true in multivariate-analysis. No significant correlation with patient prognosis could be found for the expression of the other cytokeratins and for vimentin. CONCLUSION: The expression of Ck 8/18 in SCC's of the oral cavity is an independent prognostic marker and indicates a decreased overall and progression free survival. These results provide an extended knowledge about the role of intermediary filament expression patterns in SCC's

A pilot study on peritraumatic dissociation and coping styles as risk factors for posttraumatic stress, anxiety and depression in parents after their child's unexpected admission to a Pediatric Intensive Care Unit

Aim: To study the prevalence of posttraumatic stress disorder (PTSD), anxiety and depression in parents three months after pediatric intensive care treatment of their child and examine if peritraumatic dissocation and coping styles are related to these mental health problems. Methods: This is a prospective cohort study and included parents of children unexpectedly admitted to the Pediatric Intensive Care Unit (PICU) from January 2006 to March 2007. At three months follow-up parents completed PTSD (n = 115), anxiety and depression (n = 128) questionnaires. Immediately after discharge, parents completed peritraumatic dissocation and coping questionnaires. Linear regression models with generalized estimating equations examined risk factors for mental health problems. Results: Over 10% of the parents were likely to meet criteria for PTSD and almost one quarter for subclinical PTSD. Respectively 15% to 23% of the parents reported clinically significant levels of depression and anxiety. Peritraumatic dissocation was most strongly associated with PTSD, anxiety as well as depression. Avoidance coping was primarily associated with PTSD. Conclusion: A significant number of parents have mental health problems three months after unexpected PICU treatment of their child. Improving detection and raise awareness of mental health problems is important to minimize the negative effect of these problems on parents' well-being. © 2009 Bronner et al; licensee BioMed Central Ltd

Local IL-17 Production Exerts a Protective Role in Murine Experimental Glomerulonephritis

IL-17 is a pro-inflammatory cytokine implicated in the pathogenesis of glomerulonephritis and IL-17 deficient mice are protected from nephrotoxic nephritis. However, a regulatory role for IL-17 has recently emerged. We describe a novel protective function for IL-17 in the kidney. Bone marrow chimeras were created using wild-type and IL-17 deficient mice and nephrotoxic nephritis was induced. IL-17 deficient hosts transplanted with wild-type bone marrow had worse disease by all indices compared to wild-type to wild-type bone marrow transplants (serum urea p<0.05; glomerular thrombosis p<0.05; tubular damage p<0.01), suggesting that in wild-type mice, IL-17 production by renal cells resistant to radiation is protective. IL-17 deficient mice transplanted with wild-type bone marrow also had a comparatively altered renal phenotype, with significant differences in renal cytokines (IL-10 p<0.01; IL-1β p<0.001; IL-23 p<0.01), and macrophage phenotype (expression of mannose receptor p<0.05; inducible nitric oxide synthase p<0.001). Finally we show that renal mast cells are resistant to radiation and produce IL-17, suggesting they are potential local mediators of disease protection. This is a novel role for intrinsic cells in the kidney that are radio-resistant and produce IL-17 to mediate protection in nephrotoxic nephritis. This has clinical significance as IL-17 blockade is being trialled as a therapeutic strategy in some autoimmune diseases