Analysis of the structure and function of the epidermal barrier in patients with ichthyoses-clinical and electron microscopical investigations.

BACKGROUND: Ichthyoses are pathogenetically characterized by a pronounced disorder of the epidermal barrier. Clinically, hyperkeratosis, severe scaling and erythroderma are present on the entire integument. The time-consuming therapy includes daily baths and the application of skin care products to restore the epidermal barrier. OBJECTIVES AND METHODS: To enhance the knowledge about the structure and function of the epidermal barrier in ichthyoses, we conducted clinical, biophysical and electron microscopical measurements on 46 patients with ichthyoses, including autosomal recessive ichthyoses, keratinopathic ichthyoses, X-chromosomal-recessive ichthyosis and Netherton syndrome. RESULTS: The patients displayed a significantly decreased skin hydration along with unexpectedly low transepidermal waterloss values. Electron microscopical examinations demonstrated a severe occlusion of the epidermis by lipid remnants of skin care products in the stratum corneum. We found decreased intercellular lipid lamellae and an increased undulation of the corneocyte membrane of all ichthyoses, mostly pronounced in Netherton syndrome. The lipid profiles of ichthyoses showed decreased esterified Ω-hydroxy-sphingosine (EOS) ceramide levels. CONCLUSIONS: The results demonstrate the extent of the epidermal barrier disruption in ichthyoses. In combination with the knowledge about pathogenetic causes, individually improved therapeutic options can be derived from our results. In the future, the analyses of the organization of intercellular lipid lamellae and corneocyte membrane undulation will enable improved investigations of the epidermal barrier in ichthyoses and may be used to study and evaluate possible effects of topical skin preparations.

Smoking Modifies the Genetic Risk for Early-Onset Periodontitis.

Periodontitis has low-prevalence, highly severe disease manifestations with an early onset and rapid progression. The diagnosis is based on severe destruction of the alveolar bone in adolescents and young adults. Genetic susceptibility variants and smoking are well-established risk factors, but their interactions in modifying disease susceptibility have not been studied. We aimed to identify genetic risk variants of early-onset periodontitis that unmask their effects on tobacco smoke exposure. To this end, we analyzed 79,780,573 common variants in 741 northwest Europeans diagnosed to have >30% bone loss at >2 teeth before 35 y of age, using imputed genotypes of the OmniExpress BeadChip. Never versus ever smokers were compared in a logistic regression analysis via a case-only approach. To explore the effect of tobacco smoke on the expression of the G×S-associated genes, cultures of primary gingival fibroblasts (n = 9) were exposed to cigarette smoke extract, and transcripts were quantified by reverse transcription polymerase chain reaction. We identified 16 loci for which our analysis suggested an association with G×S increased disease risk (P < 5 × 10-5). Nine loci had previously been reported to be associated with spirometric measures of pulmonary function by an earlier G×S genome-wide association study. Genome-wide significant cis expression quantitative trait loci were reported for G×S-associated single-nucleotide polymorphisms at ST8SIA1 and SOST, indicating a causal role of these genes in tobacco-related etiopathology. Notably, SOST is a negative regulator of bone growth, and ST8SIA1 has a role in tissue remodeling. Cigarette smoke extract significantly altered the expression of 2 associated genes: SSH1 (P = 5 × 10-07), which is required for NF-κB activation and innate immune responses to bacterial invasion, and ST8SIA1 (P = 0.0048). We conclude that the genetic predisposition to early-onset periodontitis is in part triggered by smoking and that tobacco smoke directly affects the expression of genes involved in bone homeostasis, tissue repair, and immune response.

Small dense LDL cholesterol in human subjects with different chronic inflammatory diseases.

BACKGROUND AND AIMS: Chronic inflammatory diseases (CID) are associated with a profound increase in cardiovascular (CV) risk resulting in reduced life expectancy. However, LDL-cholesterol is reported to be low in CID patients which is referred to as the "LDL paradoxon". The aim of the present study was to investigate whether LDL-particles in CID exhibit an increased content of the highly atherogenic small-dense LDL subfraction (sdLDL). METHODS AND RESULTS: In this prospective, single center, observational study we enrolled 141 patients with CID (RA n = 59, inflammatory bowel disease (IBD) n = 35, ankylosing spondylitis (SpA) n = 25, Psoriasis n = 22) in 2011 through 2013 to evaluate sdLDL levels before as well as 6 and 26 weeks after initiation of different anti-cytokine therapies (anti-TNFα, anti-IL-6R antibodies). sdLDL levels were compared to 141 healthy individuals in a case control design. Compared to healthy controls, all CID patients displayed a significantly higher sdLDL content within the LDL cholesterol fraction: RA 35.0 ± 9.2% (p < 0.001), SpA 42.5 ± 10.5% (p < 0.001), IBD 37.5 ± 7.1% (p < 0.001), Psoriasis 33.6 ± 4.6% (p < 0.01). Furthermore, the sdLDL/LDL ratio was significantly higher in male compared to female RA subjects (p < 0.05). Neither anti-TNFα nor anti-IL6R medication altered sdLDL levels despite a significant improvement of disease activity. CONCLUSION: In several different chronic inflammatory disease entities, LDL-cholesterol is shifted toward a pro-atherogenic phenotype due to an increased sdLDL content which might in part explain the LDL paradoxon. Since premature CV disease is a major burden of affected patients, specifically targeting lipid metabolism should be considered routinely in clinical patient care. CLINICAL TRIALS: Registration at German Clinical Trial Register (DRKS): DRKS00005285.

Serum metabolomic profiling highlights pathways associated with liver fat content in a general population sample.

BACKGROUND/OBJECTIVES: Fatty liver disease (FLD) is an important intermediate trait along the cardiometabolic disease spectrum and strongly associates with type 2 diabetes. Knowledge of biological pathways implicated in FLD is limited. An untargeted metabolomic approach might unravel novel pathways related to FLD. SUBJECTS/METHODS: In a population-based sample (n=555) from Northern Germany, liver fat content was quantified as liver signal intensity using magnetic resonance imaging. Serum metabolites were determined using a non-targeted approach. Partial least squares regression was applied to derive a metabolomic score, explaining variation in serum metabolites and liver signal intensity. Associations of the metabolomic score with liver signal intensity and FLD were investigated in multivariable-adjusted robust linear and logistic regression models, respectively. Metabolites with a variable importance in the projection >1 were entered in in silico overrepresentation and pathway analyses. RESULTS: In univariate analysis, the metabolomics score explained 23.9% variation in liver signal intensity. A 1-unit increment in the metabolomic score was positively associated with FLD (n=219; odds ratio: 1.36; 95% confidence interval: 1.27-1.45) adjusting for age, sex, education, smoking and physical activity. A simplified score based on the 15 metabolites with highest variable importance in the projection statistic showed similar associations. Overrepresentation and pathway analyses highlighted branched-chain amino acids and derived gamma-glutamyl dipeptides as significant correlates of FLD. CONCLUSIONS: A serum metabolomic profile was associated with FLD and liver fat content. We identified a simplified metabolomics score, which should be evaluated in prospective studies.

Pain and discomfort following immediate and delayed loading by overdentures in the single mandibular implant study (SMIS).

OBJECTIVES: This randomized clinical trial compares immediate and delayed loading of single implants to support mandibular overdentures. The aim of this preliminary analysis is to test the hypothesis whether patients with immediate loading will experience less pain and discomfort through the intervention than patients with delayed loading. MATERIALS AND METHODS: Edentulous patients in nine German dental schools received a midline implant with a length of 11 mm. Implants with a minimum insertion torque of 30 Ncm and an implant stability quotient of ≥60 were randomly allocated to group A for immediate loading using ball attachments or to group B for delayed loading after 3 months. Patients completed questionnaires with 100-mm visual analogue scales about the items pain, pain during chewing, swelling, bleeding, and perception of the intervention at the day of surgery and 1, 2, 3, and 7 days, thereafter. Groups were compared by Wilcoxon-Mann-Whitney tests (P ≤ 0.05). RESULTS: The questionnaires of 81 patients in group A and 74 patients in group B were completed. The medians for pain and discomfort were moderate (<30). Participants of group A felt significantly more pain from the first day and more swelling from the third day after implantation than participants of group B. The individual perception of interventions showed no significant differences between groups. CONCLUSIONS: Immediate loading evoked more postoperative pain and swelling than the two stages of delayed loading. CLINICAL RELEVANCE: Immediate loading of a single mandibular midline implant supporting overdentures should be carefully considered.

Single mandibular implant study - denture satisfaction in the elderly.

To investigate whether there are differences in patients' denture satisfaction when an implant placed in the midline of the edentulous mandible is loaded either immediately or three months later, after second-stage surgery. One hundred and fifty-eight edentulous patients received a single implant in the midline of the mandible. After randomisation, it was loaded either immediately after implant placement (N = 81, group A) or three months later, after a submerged healing phase and a second-stage surgery (N = 77, group B). Patients' denture satisfaction aspects were assessed, using visual analogue scales (VAS), before treatment, one month after implant placement during the submerged healing phase (only group B) and one and four months after implant loading. The statistical analysis was performed using the Wilcoxon signed-rank and rank-sum tests. One month after loading, a significant improvement in comfort, function and stability of the mandibular denture could be observed in both groups (P ≤ 0·05). A slight but not significant improvement was found between one and four months after loading. Patients with second-stage surgery and delayed loading rated the stability and fit of the mandibular denture as significantly better than patients who had immediate loading. A single implant in the edentulous mandible significantly increased patients' denture satisfaction. After four months, stability and fit of the mandibular denture were considered better when a delayed loading protocol had been followed. A single mandibular implant in the edentulous mandible significantly increases patients' denture satisfaction, regardless of the loading protocol.

Factors influencing the outcome (GOS) in reconstructive cranioplasty.

After performing a decompressive craniectomy, a cranioplastic surgery is usually warranted. The complications of this reconstructive procedure may differ from the initial operation. The authors of this study report on their experience to define patient-specific and procedural risk factors for possible complications following cranioplasty influencing the outcome (Glasgow Outcome Scale (GOS)), mobility, shunt dependency, and seizures. A retrospective analysis of 263 patients of all ages and both sexes who had undergone cranioplasty after craniectomy for traumatic brain injury (including chronic subdural hematoma), subarachnoidal hemorrhage (including intracerebral hemorrhage), ischemic stroke, and tumor surgery in one single center in 12 years from January 2000 to March 2012 has been carried out. A multiple logistic regression analysis was performed to identify potential risk factors (age, gender, used cranioplasty material, initial diagnosis, clipped or coil-embolized subarachnoidal hemorrhage (SAH) patients, time interval, complications especially hydrocephalus and seizures, mobility) upon the prognosis described as a dichotomized Glasgow Outcome Scale. Two hundred forty-eight patients met the study criteria. The overall complication rate after cranioplastic surgery was 18.5% (46 patients). Complications included: surgical site infection, epidural hematoma, hydrocephalus with or without former SAH, and new-onset seizures. Logistic regression analysis identified significant correlation between a low GOS (2 or 3) and postoperative seizures (OR 2.37, CI 1.35-4.18, p < 0.05), shunt-depending hydrocephalus (OR 5.83, CI 3.06-11.11, p < 0.05), and age between 51 and 70 years (OR 2.4, 95% CI 1.09-5.29, p = 0.029). However, gender, time interval between craniectomy and cranioplasty, initial diagnosis, and used cranioplasty material had no significant influence on post-cranioplasty complications as surgical site infections, hematoma, wound healing disturbance, seizures, or hydrocephalus. Evaluation of treatment modality in aneurysmal SAH clip vs. coil showed no significant relation to postoperative complications either. Complications after cranioplastic surgery are a common problem, as prognostic factors could identify a shunt-depending hydrocephalus and epilepsia to develop a major deficit after cranioplastic surgery (GOS 2 or 3). We detected a significant extra risk of people between the age of 51 and 70 years to end up in GOS level 2 or 3.

Volumetric response classification in metastatic solid tumors on MSCT: initial results in a whole-body setting.

PURPOSE: To examine technical parameters of measurement accuracy and differences in tumor response classification using RECIST 1.1 and volumetric assessment in three common metastasis types (lung nodules, liver lesions, lymph node metastasis) simultaneously. MATERIALS AND METHODS: 56 consecutive patients (32 female) aged 41-82 years with a wide range of metastatic solid tumors were examined with MSCT for baseline and follow up. Images were evaluated by three experienced radiologists using manual measurements and semi-automatic lesion segmentation. Institutional ethics review was obtained and all patients gave written informed consent. Data analysis comprised interobserver variability operationalized as coefficient of variation and categorical response classification according to RECIST 1.1 for both manual and volumetric measures. Continuous data were assessed for statistical significance with Wilcoxon signed-rank test and categorical data with Fleiss kappa. RESULTS: Interobserver variability was 6.3% (IQR 4.6%) for manual and 4.1% (IQR 4.4%) for volumetrically obtained sum of relevant diameters (p<0.05, corrected). 4-8 patients' response to therapy was classified differently across observers by using volumetry compared to standard manual measurements. Fleiss kappa revealed no significant difference in categorical agreement of response classification between manual (0.7558) and volumetric (0.7623) measurements. CONCLUSION: Under standard RECIST thresholds there was no advantage of volumetric compared to manual response evaluation. However volumetric assessment yielded significantly lower interobserver variability. This may allow narrower thresholds for volumetric response classification in the future.

Pancreatic carcinoma cell lines reflect frequency and variability of cancer stem cell markers in clinical tissue.

BACKGROUND: Pancreatic cancer is one of the most deadly malignancies with insufficient therapeutic options and poor outcome. Cancer stem cells (CSCs) are thought to be responsible for progression and therapy resistance. We investigated the potential of pancreatic cell lines for CSC research by analyzing to what extent they contain CSC populations and how representative these are compared to clinical tissue. METHODS: Six pancreatic cancer cell lines were analyzed by flow cytometry for CD326, CD133, CD44, CD24, CXCR4 and ABCG2. Subsequently, 70 primary pancreatic tissues were evaluated for CD326, CD133 and CD44 by immunohistochemistry. RESULTS: All the cell lines but one showed a stable expression pattern throughout biological replicates. Marker expression in clinical tissue of CD44 distinguished normal patients from pancreatic carcinoma patients with a sensitivity of 50% at 80% specificity and metastasized from nonmetastasized carcinomas with 69% sensitivity at 100% specificity. CONCLUSIONS: Our results indicate a link between elevated CD44 expression, malignancy and metastasis of pancreatic tissue. Furthermore, individual pancreatic cell lines show a substantial amount of cells with CSC properties which is comparable with interpatient variability detected in primary tissue. These pancreatic cancer cell lines could thus serve for urgently needed pharmacological CSC in vitro research.

Lung, liver and lymph node metastases in follow-up MSCT: comprehensive volumetric assessment of lesion size changes.

PURPOSE: To investigate measurement accuracy in terms of precision and inter-rater variability in the simultaneous volumetric assessment of lung, liver and lymph node metastasis size change over time in comparison to RECIST 1.1. MATERIALS AND METHODS: Three independent readers evaluated multislice CT data from clinical follow-up studies (chest/abdomen) in 50 patients with metastases. A total of 117 lung, 77 liver and 97 lymph node metastases were assessed manually (RECIST 1.1) and by volumetry with semi-automated software. The quality of segmentation and need for manual adjustments were recorded. Volumes were converted to effective diameters to allow comparison to RECIST. For statistical assessment of precision and interobserver agreement, the Wilcoxon-signed rank test and Bland-Altman plots were utilized. RESULTS: The quality of segmentation after manual correction was acceptable to excellent in 95 % of lesions and manual corrections were applied in 21 - 36 % of all lesions, most predominantly in lymph nodes. Mean precision was 2.6 - 6.3 % (manual) with 0.2 - 1.5 % (effective) relative measurement deviation (p <.001). Inter-reader median variation coefficients ranged from 9.4 - 12.8 % (manual) and 2.9 - 8.2 % (volumetric) for different lesion types (p < .001). The limits of agreement were ± 9.8 to ± 11.2 % for volumetric assessment. CONCLUSION: Superior precision and inter-rater variability of volumetric over manual measurement of lesion change over time was demonstrated in a whole body setting.

Clinical lymph node staging--influence of slice thickness and reconstruction kernel on volumetry and RECIST measurements.

PURPOSE: Therapy response evaluation in oncological patient care requires reproducible and accurate image evaluation. Today, common standard in measurement of tumour growth or shrinkage is one-dimensional RECIST 1.1. A proposed alternative method for therapy monitoring is computer aided volumetric analysis. In lung metastases volumetry proved high reliability and accuracy in experimental studies. High reliability and accuracy of volumetry in lung metastases has been proven. However, other metastatic lesions such as enlarged lymph nodes are far more challenging. The aim of this study was to investigate the reproducibility of semi-automated volumetric analysis of lymph node metastases as a function of both slice thickness and reconstruction kernel. In addition, manual long axis diameters (LAD) as well as short axis diameters (SAD) were compared to automated RECIST measurements. MATERIALS AND METHODS: Multislice-CT of the chest, abdomen and pelvis of 15 patients with lymph node metastases of malignant melanoma were included. Raw data were reconstructed using different slice thicknesses (1-5 mm) and varying reconstruction kernels (B20f, B40f, B60f). Volume and RECIST measurements were performed for 85 lymph nodes between 10 and 60 mm using Oncology Prototype Software (Fraunhofer MEVIS, Siemens, Germany) and were compared to a defined reference volume and diameter by calculating absolute percentage errors (APE). Variability of the lymph node sizes was computed as relative measurement differences, precision of measurements was computed as relative measurement deviation. RESULTS: Mean absolute percentage error (APE) for volumetric analysis varied between 3.95% and 13.8% and increased significantly with slice thickness. Differences between reconstruction kernels were not significant, however, a trend towards middle soft tissue kernel could be observed.. Between automated and manual short axis diameter (SAD, RECIST 1.1) and long axis diameter (LAD, RECIST 1.0) no significant differences were found. The most unsatisfactory segmentation results occurred in higher slice thickness (3 and 5 mm) and sharp tissue kernel. CONCLUSION: Volumetric analysis of lymph nodes works satisfying in a clinical setting. Thin slice reconstructions (≤3 mm) and a middle soft tissue reconstruction kernel are recommended. LAD and SAD did not show significant differences regarding APE. Automated RECIST measurement showed lower APE than manual measurement in trend.

Detection of artificial air space opacities with digital radiography: ex vivo study on enhanced latitude post-processing.

PURPOSE: To evaluate in a.-p. digital chest radiograms of an ex vivo system if increased latitude and enhanced image detail contrast (EVP) improve the accuracy of detecting artificial air space opacities in parts of the lung that are superimposed by the diaphragm. MATERIALS AND METHODS: 19 porcine lungs were inflated inside a chest phantom, prepared with 20-50 ml gelatin-stabilized liquid to generate alveolar air space opacities, and examined with direct radiography (3.0 × 2.5 k detector/ 125 kVp/ 4 mAs). 276 a.-p. images with and without EVP of 1.0-3.0 were presented to 6 observers. 8 regions were read for opacities, the reference was defined by CT. Statistics included sensitivity/specificity, interobserver variability, and calculation of Az (area under ROC curve). RESULTS: Behind the diaphragm (opacities in 32/92 regions), the median sensitivity increased from 0.35 without EVP to 0.53-0.56 at EVP 1.5-3.0 (significant in 5/6 observers). The specificity decreased from 0.96 to 0.90 (significant in 6/6), and the Az value and interobserver correlation increased from 0.66 to 0.74 and 0.39 to 0.48, respectively. Above the diaphragm, the median sensitivity for artificial opacities (136/276 regions) increased from 0.71 to 0.77-0.82 with EVP (significant in 4/6 observers). The specificity and Az value decreased from 0.76 to 0.62 and 0.74 to 0.70, respectively, (significant in 3/6). CONCLUSION: In this ex vivo experiment, EVP improved the diagnostic accuracy for artificial air space opacities in the superimposed parts of the lung (area under the ROC curve). Above the diaphragm, the accuracy was not affected due to a tradeoff in sensitivity/specificity.

Precision of computer-aided volumetry of artificial small solid pulmonary nodules in ex vivo porcine lungs.

The purpose of this study was to investigate the precision of CT-based volumetric measurements of artificial small pulmonary nodules under ex vivo conditions. We implanted 322 artificial nodules in 23 inflated ex vivo porcine lungs in a dedicated chest phantom. The lungs were examined with a multislice spiral CT (20 mAs, collimation 16x0.75 mm, 1 mm slice thickness, 0.7 mm increment). A commercial volumetry software package (LungCARE VA70C-W; Siemens, Erlangen, Germany) was used for volume analysis in a semi-automatic and a manual corrected mode. After imaging, the lungs were dissected to harvest the nodules for gold standard determination. The volumes of 202 solitary, solid and well-defined lesions without contact with the pleura, greater bronchi or vessels were compared with the results of volumetry. A mean nodule diameter of 8.3 mm (+/-2.1 mm) was achieved. The mean relative deviation from the true lesion volume was -9.2% (+/-10.6%) for semi-automatic and -0.3% (+/-6.5%) for manual corrected volumetry. The subgroup of lesions from 5 mm to <10 mm in diameter showed a mean relative deviation of -8.7% (+/-10.9%) for semi-automatic volumetry and -0.3% (+/-6.9%) for manually corrected volumetry. We conclude that the presented software allowed for precise volumetry of artificial nodules in ex vivo lung tissue. This result is comparable to the findings of previous in vitro studies.

Interobserver-variability of lung nodule volumetry considering different segmentation algorithms and observer training levels.

OBJECTIVE: The aim of this study was to investigate the interobserver variability of CT based diameter and volumetric measurements of artificial pulmonary nodules. A special interest was the consideration of different measurement methods, observer experience and training levels. MATERIALS AND METHODS: For this purpose 46 artificial small solid nodules were examined in a dedicated ex-vivo chest phantom with multislice-spiral CT (20 mAs, 120 kV, collimation 16 mm x 0.75 mm, table feed 15 mm, reconstructed slice thickness 1mm, reconstruction increment 0.7 mm, intermediate reconstruction kernel). Two observer groups of different radiologic experience (0 and more than 5 years of training, 3 observers each) analysed all lesions with digital callipers and 2 volumetry software packages (click-point depending and robust volumetry) in a semi-automatic and manually corrected mode. For data analysis the variation coefficient (VC) was calculated in per cent for each group and a Wilcoxon test was used for analytic statistics. RESULTS: Click-point robust volumetry showed with a VC of <0.01% in both groups the smallest interobserver variability. Between experienced and un-experienced observers interobserver variability was significantly different for diameter measurements (p=0.023) but not for semi-automatic and manual corrected volumetry. A significant training effect was revealed for diameter measurements (p=0.003) and semi-automatic measurements of click-point depending volumetry (p=0.007) in the un-experienced observer group. CONCLUSIONS: Compared to diameter measurements volumetry achieves a significantly smaller interobserver variance and advanced volumetry algorithms are independent of observer experience.

Selective affection of hippocampal CA-1 neurons in patients with transient global amnesia without long-term sequelae.

The aetiology, pathomechanisms and anatomical correlates of transient global amnesia (TGA) still remain obscure. Recently, focal MR-signal diffusion-weighted imaging (DWI) changes in the hippocampus have been described in patients with TGA, but the exact localization, long term outcome and pathophysiological nature of these lesions still remain unknown. The topography and time course of hippocampal DWI lesions in 41 TGA patients was studied using serial 3 T high-resolution MR-imaging and correlated to clinical and neuropsychometric results. Of these, 29 patients showed 36 DWI lesions with corresponding T(2) lesions in the hippocampus within a time window of 48 h after onset. Almost all lesions (94%; 34/36) were selectively found in the CA-1 sector (Sommer sector) of the hippocampal cornu ammonis. Most DWI lesions (8/10) were already detectable in the peri-acute phase <6 h after onset of symptoms. A follow-up study 4-6 months after the episode did not show evidence for residual structural sequelae of these lesions (n = 20/20). A venous MR angiography of the intracranial dural sinus showed an asymmetric venous drainage in 21/24 (88%) patients. In 11/16 (69%) patients with unilateral lesions, the asymmetry corresponded to the side of the DWI lesion. Significant episodic verbal memory deficits in the acute phase (n = 14/18) were associated with lesions of the dominant hemisphere while impairment of visuospatial memory was associated with lesions of the non-dominant hemisphere. Persistent neuropsychological sequelae were not detected 4-6 months after the episode (n = 16). This is the first prospective study combining high-resolution imaging and neuropsychometry analysing the detailed functional anatomy and outcome of hippocampal DWI/T(2) lesions in TGA supporting the view the TGA being a benign transient disorder. The TGA can be considered a model for a focal transient perturbation of memory circuits in the temporo-mesial region.