Oxidative stress and inflammation response after nanoparticle exposure: differences between human lung cell monocultures and an advanced three-dimensional model of the human epithelial airways

Combustion-derived and manufactured nanoparticles (NPs) are known to provoke oxidative stress and inflammatory responses in human lung cells; therefore, they play an important role during the development of adverse health effects. As the lungs are composed of more than 40 different cell types, it is of particular interest to perform toxicological studies with co-cultures systems, rather than with monocultures of only one cell type, to gain a better understanding of complex cellular reactions upon exposure to toxic substances. Monocultures of A549 human epithelial lung cells, human monocyte-derived macrophages and monocyte-derived dendritic cells (MDDCs) as well as triple cell co-cultures consisting of all three cell types were exposed to combustion-derived NPs (diesel exhaust particles) and to manufactured NPs (titanium dioxide and single-walled carbon nanotubes). The penetration of particles into cells was analysed by transmission electron microscopy. The amount of intracellular reactive oxygen species (ROS), the total antioxidant capacity (TAC) and the production of tumour necrosis factor (TNF)-alpha and interleukin (IL)-8 were quantified. The results of the monocultures were summed with an adjustment for the number of each single cell type in the triple cell co-culture. All three particle types were found in all cell and culture types. The production of ROS was induced by all particle types in all cell cultures except in monocultures of MDDCs. The TAC and the (pro-)inflammatory reactions were not statistically significantly increased by particle exposure in any of the cell cultures. Interestingly, in the triple cell co-cultures, the TAC and IL-8 concentrations were lower and the TNF-alpha concentrations were higher than the expected values calculated from the monocultures. The interplay of different lung cell types seems to substantially modulate the oxidative stress and the inflammatory responses after NP exposure.

Non-fatal cardiovascular outcome in patients with posttraumatic stress symptoms caused by myocardial infarction

Objectives Posttraumatic stress disorder (PTSD) prospectively increases the risk of incident cardiovascular disease (CVD) independent of other risk factors in otherwise healthy individuals. Between 10% and 20% of patients develop PTSD related to the traumatic experience of myocardial infarction (MI). We investigated the hypothesis that PTSD symptoms caused by MI predict adverse cardiovascular outcome. Methods We studied 297 patients (61 ± 10 years, 83% men) who self-rated PTSD symptoms attributable to a previous index MI. Non-fatal CVD-related hospital readmissions (i.e. recurrent MI, elective and non-elective intracoronary stenting, bypass surgery, pacemaker implantation, cardiac arrhythmia, cerebrovascular event) were assessed at follow-up. Cox proportional hazard models controlled for demographic factors, coronary heart disease severity, major CVD risk factors, cardiac medication, and mental health treatment. Results Forty-three patients (14.5%) experienced an adverse event during a mean follow-up of 2.8 years (range 1.3–3.8). A 10 point higher level in the PTSD symptom score (mean 8.8 ± 9.0, range 0–47) revealed a hazard ratio (HR) of 1.42 (95% CI 1.07–1.88) for a CVD-related hospital readmission in the fully adjusted model. A similarly increased risk (HR 1.45, 95% CI 1.07–1.97) emerged for patients with a major or unscheduled CVD-related readmission (i.e. when excluding patients with elective stenting). Conclusions Elevated levels of PTSD symptoms caused by MI may adversely impact non-fatal cardiovascular outcome in post-MI patients independent of other important prognostic factors. The possible importance of PTSD symptoms as a novel prognostic psychosocial risk factor in post-MI patients warrants further study.

Wear of double crown systems: electroplated vs. casted female part

The wear of telescopic crowns is a common problem often reducing the patient's satisfaction with the denture and resulting in a renewal of the denture. The study aims to compare the wear behavior of conical crowns using electroplated copings (group E ) with standard telescopic crowns with cast female parts (group C).

Changes in retention force with electroplated copings on conical crowns: a comparison of gold and zirconia primary crowns

The aim of this study was to examine the wear behavior of conical crowns with electroplated gold copings that are used to connect implants and teeth to a removable denture. Gold alloy and zirconium dioxide ceramic crowns were compared.

Telescopic crowns: extra-oral and intra-oral retention force measurement--in vitro/in vivo correlation

This study deals with the determination of the retentive forces of telescopic crowns measured extra- and intra-orally and the correlation of these values.

Clinical retention force development of double crowns

This study deals with the development of the retentive forces of double crowns intraorally measured. Twenty-five combined fixed-removable prostheses with a total of 84 double crowns were included in the study. The intraoral measurement was performed at 72 defined measuring points directly adjacent to the double crowns of the dentures. The measurement was performed 4-6 weeks (baseline), 6 months (recall 1), and 18 months (recall 2) after the insertion of the restoration. A specifically designed measuring device was used. The median values for the single measuring points reached 4.705 N at the baseline, 5.190 N after 6 months, and 3.740 N after 18 months. The measured values were analyzed according to differences between the median retention forces at the three defined points in time. The statistical analysis of the median values showed no statistical difference for the retention force change after 6 months but for the decrease until the second recall (Mann-Whitney test). The retention force per denture was calculated by a summation of the single measuring points. At the baseline, 12.9 N was reached. The forces did only decrease slightly and were not statistically significant. The results indicate that retention force values of double crowns, measured intraorally at the patient, do not relevantly change clinically within the first 1.5 years. Within the limitations of this study, it can be stated that wear does not influence the retentive forces of double crowns within the first 18 months. After this period the retention force should be still sufficient for denture retention.

Stromal cell-associated expression of kallikrein-related peptidase 6 (KLK6) indicates poor prognosis of ovarian cancer patients

Several members of the human kallikrein-related peptidase family, including KLK6, are up-regulated in ovarian cancer. High KLK6 mRNA or protein expression, measured by quantitative polymerase chain reaction and enzyme-linked immunoassay, respectively, was previously found to be associated with a shortened overall and progression-free survival (OS and PFS, respectively). In the present study, we aimed at analyzing KLK6 protein expression in ovarian cancer tissue by immunohistochemistry. Using a newly developed monospecific polyclonal antibody, KLK6 immunoexpression was initially evaluated in normal tissues. We observed strong staining in the brain and moderate staining in the kidney, liver, and ovary, whereas the pancreas and the skeletal muscle were unreactive, which is in line with previously published results. Next, both tumor cell- and stromal cell-associated KLK6 immunoexpression were analyzed in tumor tissue specimens of 118 ovarian cancer patients. In multivariate Cox regression analysis, only stromal cell-associated expression, besides the established clinical parameters FIGO stage and residual tumor mass, was found to be statistically significant for OS and PFS [high vs. low KLK6 expression; hazard ratio (HR), 1.92; p=0.017; HR, 1.80; p=0.042, respectively]. These results indicate that KLK6 expressed by stromal cells may considerably contribute to the aggressiveness of ovarian cancer.

Maintenance of skills, competencies, and performance in allergy and clinical immunology: time to lay the foundation for a universal approach

Allergist/clinical immunologist maintenance of certification and training program reaccreditation are mandatory in some countries. The World Allergy Organization conducted surveys in 2009 and 2011 to assess where such programs were available and to promote the establishment of such programs on a global level. This was done with the presumption that after such an "inventory," World Allergy Organization could offer guidance to its Member Societies on the promotion of such programs to assure the highest standards of practice in the field of allergy and clinical immunology. This review draws on the experience of countries where successful programs are in place and makes recommendations for those wishing to implement such programs for the specialty.

Antibiotic susceptibility patterns and resistance genes of starter cultures and probiotic bacteria used in food

A survey of starter and probiotic cultures was carried out to determine the current antibiotic resistance situation in microbial food additives in Switzerland. Two hundred isolates from 90 different sources were typed by molecular and other methods to belong to the genera Lactobacillus (74 samples), Staphylococcus (33 samples), Bifidobacterium (6 samples), Pediococcus (5 samples), or were categorized as lactococci or streptococci (82 samples). They were screened for phenotypic resistances to 20 antibiotics by the disk diffusion method. Twenty-seven isolates exhibiting resistances that are not an intrinsic feature of the respective genera were further analyzed by microarray hybridization as a tool to trace back phenotypic resistances to specific genetic determinants. Their presence was finally verified by PCR amplification or Southern hybridization. These studies resulted in the detection of the tetracycline resistance gene tet(K) in 5 Staphylococcus isolates used as meat starter cultures, the tetracycline resistance gene tet(W) in the probiotic cultures Bifidobacterium lactis DSM 10140 and Lactobacillus reuteri SD 2112 (residing on a plasmid), and the lincosamide resistance gene lnu(A) (formerly linA) in L. reuteri SD 2112.

Consequences of depleted SERCA2-gated calcium stores in the skin

Sarco(endo)plasmic reticulum Ca2+-ATPase isoform 2 (SERCA2) pumps belong to the family of Ca2+-ATPases responsible for the maintenance of calcium in the endoplasmic reticulum. In epidermal keratinocytes, SERCA2-controlled calcium stores are involved in cell cycle exit and onset of terminal differentiation. Hence, their dysfunction was thought to provoke impaired keratinocyte cohesion and hampered terminal differentiation. Here, we assessed cultured keratinocytes and skin biopsies from a canine family with an inherited skin blistering disorder. Cells from lesional and phenotypically normal areas of one of these dogs revealed affected calcium homeostasis due to depleted SERCA2-gated stores. In phenotypically normal patient cells, this defect compromised upregulation of p21(WAF1) and delayed the exit from the cell cycle. Despite this abnormality it failed to impede the terminal differentiation process in the long term but instead coincided with enhanced apoptosis and appearance of chronic wounds, suggestive of secondary mutations. Collectively, these findings provide the first survey on phenotypic consequences of depleted SERCA-gated stores for epidermal homeostasis that explain how depleted SERCA2 calcium stores provoke focal lesions rather than generalized dermatoses, a phenotype highly reminiscent of the human genodermatosis Darier disease.

Pemphigus vulgaris identifies plakoglobin as key suppressor of c-Myc in the skin

The autoimmune disease pemphigus vulgaris (PV) manifests as loss of keratinocyte cohesion triggered by autoantibody binding to desmoglein (Dsg)3, an intercellular adhesion molecule of mucous membranes, epidermis, and epidermal stem cells. Here we describe a so far unknown signaling cascade activated by PV antibodies. It extends from a transient enhanced turn over of cell surface-exposed, nonkeratin-anchored Dsg3 and associated plakoglobin (PG), through to depletion of nuclear PG, and as one of the consequences, abrogation of PG-mediated c-Myc suppression. In PV patients (6/6), this results in pathogenic c-Myc overexpression in all targeted tissues, including the stem cell compartments. In summary, these results show that PV antibodies act via PG to abolish the c-Myc suppression required for both maintenance of epidermal stem cells in their niche and controlled differentiation along the epidermal lineage. Besides a completely novel insight into PV pathogenesis, these data identify PG as a potent modulator of epithelial homeostasis via its role as a key suppressor of c-Myc.