NRF2 Shortage in Human Skin Fibroblasts Dysregulates Matrisome Gene Expression and Affects Collagen Fibrillogenesis

NRF2 is a master regulator of the antioxidative response that was recently proposed as a potential regulator of extracellular matrix (ECM) gene expression. Fibroblasts are major ECM producers in all connective tissues, including the dermis. A better understanding of NRF2-mediated ECM regulation in skin fibroblasts is thus of great interest for skin homeostasis maintenance and aging protection. In this study, we investigate the impact of NRF2 downregulation on matrisome gene expression and ECM deposits in human primary dermal fibroblasts. RNA-sequencing‒based transcriptome analysis of NRF2 silenced dermal fibroblasts shows that ECM genes are the most regulated gene sets, highlighting the relevance of the NRF2-mediated matrisome program in these cells. Using complementary light and electron microscopy methods, we show that NRF2 deprivation in dermal fibroblasts results in reduced collagen I biosynthesis and impacts collagen fibril deposition. Moreover, we identify ZNF469, a putative transcriptional regulator of collagen biosynthesis, as a target of NRF2. Both ZNF469 silenced fibroblasts and fibroblasts derived from Brittle Corneal Syndrome patients carrying variants in ZNF469 gene show reduced collagen I gene expression. Our study shows that NRF2 orchestrates matrisome expression in human skin fibroblasts through direct or indirect transcriptional mechanisms that could be prioritized to target dermal ECM homeostasis in health and disease.

PGC-1s Shape Epidermal Physiology by Modulating Keratinocyte Proliferation and Terminal Differentiation

Skin plays central roles in systemic physiology, and it undergoes significant functional changes during aging. Members of the peroxisome proliferator-activated receptor-gamma coactivator (PGC-1) family (PGC-1s) are key regulators of the biology of numerous tissues, yet we know very little about their impact on skin functions. Global gene expression profiling and gene silencing in keratinocytes uncovered that PGC-1s control the expression of metabolic genes as well as that of terminal differentiation programs. Glutamine emerged as a key substrate promoting mitochondrial respiration, keratinocyte proliferation, and the expression of PGC-1s and terminal differentiation programs. Importantly, gene silencing of PGC-1s reduced the thickness of a reconstructed living human epidermal equivalent. Exposure of keratinocytes to a salicylic acid derivative potentiated the expression of PGC-1s and terminal differentiation genes and increased mitochondrial respiration. Overall, our results show that the PGC-1s are essential effectors of epidermal physiology, revealing an axis that could be targeted in skin conditions and aging.

Milk intake and incident stroke and CHD in populations of European descent: a Mendelian randomisation study

Higher milk intake has been associated with a lower stroke risk, but not with risk of CHD. Residual confounding or reverse causation cannot be excluded. Therefore, we estimated the causal association of milk consumption with stroke and CHD risk through instrumental variable (IV) and gene-outcome analyses. IV analysis included 29 328 participants (4611 stroke; 9828 CHD) of the European Prospective Investigation into Cancer and Nutrition (EPIC)-CVD (eight European countries) and European Prospective Investigation into Cancer and Nutrition-Netherlands (EPIC-NL) case-cohort studies. rs4988235, a lactase persistence (LP) SNP which enables digestion of lactose in adulthood was used as genetic instrument. Intake of milk was first regressed on rs4988235 in a linear regression model. Next, associations of genetically predicted milk consumption with stroke and CHD were estimated using Prentice-weighted Cox regression. Gene-outcome analysis included 777 024 participants (50 804 cases) from MEGASTROKE (including EPIC-CVD), UK Biobank and EPIC-NL for stroke, and 483 966 participants (61 612 cases) from CARDIoGRAM, UK Biobank, EPIC-CVD and EPIC-NL for CHD. In IV analyses, each additional LP allele was associated with a higher intake of milk in EPIC-CVD (β = 13·7 g/d; 95 % CI 8·4, 19·1) and EPIC-NL (36·8 g/d; 95 % CI 20·0, 53·5). Genetically predicted milk intake was not associated with stroke (HR per 25 g/d 1·05; 95 % CI 0·94, 1·16) or CHD (1·02; 95 % CI 0·96, 1·08). In gene-outcome analyses, there was no association of rs4988235 with risk of stroke (OR 1·02; 95 % CI 0·99, 1·05) or CHD (OR 0·99; 95 % CI 0·95, 1·03). Current Mendelian randomisation analysis does not provide evidence for a causal inverse relationship between milk consumption and stroke or CHD risk.

Oxidative damage prevention in human skin and sensory neurons by a salicylic acid derivative

BACKGROUND

Increased protein carbonylation is a hallmark of oxidative stress, protein homeostasis dysregulation and aging in the nervous system and skin. Sensory neurons interact with skin cells and are involved in skin homeostasis. We have previously reported that the 5-octanoyl salicylic acid (C8-SA), a salicylic acid derivative, increased C. elegans lifespan and delayed the accumulation of carbonylated proteins, through the stimulation of autophagy.

OBJECTIVES

In this study we aimed to investigate if C8-SA protects human sensory neurons and human skin from extrinsic oxidative stressors as an approach to delay skin aging.

METHODS

In vitro reconstituted human epidermis innervated with hiPSc-derived human sensory neurons, as well as ex vivo human organotypic full skin models were used. The fully differentiated sensory neurons were pretreated with C8-SA before oxidative stress induction. Skin explants were maintained in culture and treated topically with C8-SA before the application of urban pollutants. Carbonylated proteins were detected using amino-oxy functionalized fluorophores and quantified. Chaperone mediated autophagy was monitored with LAMP2A immunofluorescence. Inflammation, ROS detoxification and autophagy were assessed by RT-PCR.

RESULTS

C8-SA prevented the accumulation of carbonylated proteins, both in human sensory neurons and skin explants. C8-SA stimulated chaperone-mediated autophagy and modulated NRF2 antioxidant response genes, as well as catalase enzymatic activity.

CONCLUSIONS

C8-SA acts at two levels to protect skin against oxidative stress: 1) it prevents protein oxidation by stimulating endogenous antioxidant defense and 2) it increases the clearance of oxidized proteins by stimulating chaperone-mediated autophagy. These results suggest that C8-SA maintains skin health in urban polluted environments.

Does high adherence to contact precautions lead to low in-hospital transmission of multi-drug-resistant micro-organisms in the endemic setting?

BACKGROUND

Conflicting results have been published on the impact of contact precautions (CPs) on reduction of transmission of multi-drug-resistant micro-organisms (MDROs) in the endemic setting. Ambiguous definitions coupled with low adherence partly explain these differences.

AIM

We prospectively monitored the level of adherence to CPs and aimed to relate it to in-hospital transmission of MDROs.

METHODS

Between January 2016 and March 2018, all patients under CPs underwent continuous monitoring of adherence to CPs by routine on-site visits on days 0, 3 and 7 after initiating CPs using a standardized checklist. The protocol included 10 interventions that were routinely checked such as CP sign at the door as well as wearing of gowns and gloves upon entry to the patient room. Patients requiring CPs were defined as colonized or infected with MDROs (meticillin-resistant Staphylococcus aureus (MRSA), non-Escherichia coli extended-spectrum beta lactamase (ESBL) Enterobacterales, vancomycin-resistant enterococci (VRE) and carbapenem-resistant Gram-negative micro-organisms (CRGN)) as well as patients infected with respiratory viruses, norovirus, scabies and hypervirulent strains of Clostridioides difficile.

FINDINGS

Overall, data from 13,756 CP records from 1378 visits of 812 patients were analysed. Adherence varied between 93% and 100% for each intervention, except for "separate space for contaminated material" with an adherence of 5.3-6.1%. The incidence of in-hospital transmission during the study period was extremely low for MRSA, VRE, non-E.coli ESBL Enterobacterales and CRGN with 0.00-0.064 cases/1000 patient days.

CONCLUSION

High adherence coupled with continuous monitoring of CPs correlated with a very low in-hospital transmission rate. These results indicate that CPs are highly effective if routine monitoring of adherence is implemented.

Femoral Cementation in Knee Arthroplasty-A Comparison of Three Cementing Techniques in a Sawbone Model Using the ATTUNE Knee

Femoral component loosening is a rare but severe complication in total knee arthroplasty. Former studies have repeatedly demonstrated radiolucent lines behind the ventral and dorsal anchoring shields of the femoral components, which has led us to investigate this matter further. Therefore, three different cementing techniques were tested in a group of nine Sawbone samples each. These differed in the amount of cement applied on the femoral component as well as in the pressure application. Computed tomography was performed to evaluate and classify the cement penetration into the bone adjacent to the prosthesis according to the zones defined by the Knee Society scoring system. The results show significantly deeper cement penetration in all zones when a pressurizer is used. In the other two groups, no significant difference in the dorsal bevel cement penetration was noted. Additionally, no difference in ventral and dorsal cement penetrations (Zones 1 and 4) was delineated. In contrast, there was a significant difference in both the ventral bevel (Zone 2) as well as the distal anchoring surface (Zones 5-7). The use of a pressurizer results in greater cement penetration into all anchoring areas. Completely covering the component back surface results in a significantly higher penetration, which is mainly due to differences in volume. These data show significantly improved cementation results when using a pressurizer. Whether this improves the biomechanical properties and ultimately the revision rate requires further investigation.

Multi-dimensional computational pipeline for large-scale deep screening of compound effect assessment: an in silico case study on ageing-related compounds

Designing alternative approaches to efficiently screen chemicals on the efficacy landscape is a challenging yet indispensable task in the current compound profiling methods. Particularly, increasing regulatory restrictions underscore the need to develop advanced computational pipelines for efficacy assessment of chemical compounds as alternative means to reduce and/or replace in vivo experiments. Here, we present an innovative computational pipeline for large-scale assessment of chemical compounds by analysing and clustering chemical compounds on the basis of multiple dimensions-structural similarity, binding profiles and their network effects across pathways and molecular interaction maps-to generate testable hypotheses on the pharmacological landscapes as well as identify potential mechanisms of efficacy on phenomenological processes. Further, we elucidate the application of the pipeline on a screen of anti-ageing-related compounds to cluster the candidates based on their structure, docking profile and network effects on fundamental metabolic/molecular pathways associated with the cell vitality, highlighting emergent insights on compounds activities based on the multi-dimensional deep screen pipeline.

A salicylic acid derivative extends the lifespan of Caenorhabditis elegans by activating autophagy and the mitochondrial unfolded protein response

Plant extracts containing salicylates are probably the most ancient remedies to reduce fever and ease aches of all kind. Recently, it has been shown that salicylates activate adenosine monophosphate‐activated kinase (AMPK), which is now considered as a promising target to slow down aging and prevent age‐related diseases in humans. Beneficial effects of AMPK activation on lifespan have been discovered in the model organism Caenorhabditis elegans (C. elegans). Indeed, salicylic acid and acetylsalicylic acid extend lifespan in worms by activating AMPK and the forkhead transcription factor DAF‐16/FOXO. Here, we investigated whether another salicylic acid derivative 5‐octanoyl salicylic acid (C8‐SA), developed as a controlled skin exfoliating ingredient, had similar properties using C. elegans as a model. We show that C8‐SA increases lifespan of C. elegans and that a variety of pathways and genes are required for C8‐SA‐mediated lifespan extension. C8‐SA activates AMPK and inhibits TOR both in nematodes and in primary human keratinocytes. We also show that C8‐SA can induce both autophagy and the mitochondrial unfolded protein response (UPR^mit) in nematodes. This induction of both processes is fully required for lifespan extension in the worm. In addition, we found that the activation of autophagy by C8‐SA fails to occur in worms with compromised UPR^mit, suggesting a mechanistic link between these two processes. Mutants that are defective in the mitochondrial unfolded protein response exhibit constitutive high autophagy levels. Taken together, these data therefore suggest that C8‐SA positively impacts longevity in worms through induction of autophagy and the UPR^mit.

Mapping the electric field distribution of tightly focused cylindrical vector beams with gold nanorings

In this paper gold nanorings (NRs) are applied as particularly well-suited sensing elements for mapping the radially symmetric electric fields in the high numerical aperture focus of cylindrical vector beams. The optical properties of gold nanorings are analyzed by a combination of extinction and single particle dark field spectroscopy as well as confocal photoluminescence (PL) imaging. The results are compared to numerical calculations. The in-plane components in the focus of the cylindrical vector beams are estimated through the PL intensity distributions of the NRs. The optimum overlap between the structure and excitation is visualized by a narrow centre spot in the far-field PL scan.

Longevity effect of a polysaccharide from Chlorophytum borivilianum on Caenorhabditis elegans and Saccharomyces cerevisiae

The traditional Indian medicine, Ayurveda, provides insights and practical solutions towards a healthy life style. Rasayana is a branch of Ayurveda known for preserving and promoting health, enhancing the quality of life and delaying the aging process. In the traditional knowledge, the Rasayana herb, Chlorophytum borivilianum (C. borivilanum) is regarded as a general health promoting tonic that delays aging and increases lifespan, cognitive function and physical strength. Aging is a complex and multifactorial physiological phenomenon that manifests itself over a wide range of biological systems, tissues, and functions. Longevity is an obvious marker of physiological aging. Simple model systems such as the single-cell budding yeast Saccharomyces cerevisiae (S. cerevisiae) and the nematode, Caenorhabditis elegans (C. elegans) are widely used to study the aging process and longevity. Here, we show that a polysaccharide fraction obtained from C. borivilianum increases the lifespan of S. cerevisiae and C. elegans, using an automated screening platform (Chronoscreen^TM). Chemical analysis of this extract revealed a low molecular weight polysaccharide of 1000 Da, predominantly comprising Glu1→6Glu linkage. This polysaccharide showed significant dose-dependent extension of the median lifespan of S. cerevisiae by up to 41% and of the median lifespan of C. elegans by up to 10%. Taking cue from these results and the traditionally described benefits of Rasayanas on skin rejuvenation, we tested in vitro the polysaccharide for potential skin benefits. In a keratinocyte culture, we observed that this polysaccharide increased cell proliferation significantly, and induced synthesis of hyaluronic acid (HA), a well-known extracellular matrix component. Furthermore, when added to culture medium of human reconstructed epidermis, we observed an enhanced production of epidermal markers, e.g. CD44 and HA that are otherwise diminished in aged skin. Together, these results suggest that in addition to life-span extension of S. cerevisiae and C. elegans, a polysaccharide from the Rasayana herb, C. borivilianum may have beneficial effects on skin aging parameters.

Femoral rotation in total knee arthroplasty: a comparison of patient individualized jigs with gap balancing in relation to anatomic landmarks

PURPOSE

The purpose of our study was to compare the accuracy of the rotational position of the femoral component in total knee arthroplasty aligned with patient individualized jigs (PSJ) to a gap balancing technique (GBT).

METHODS

A consecutive series of 21 osteoarthritic patients were treated with 22 cruciate-retaining total knee prostheses. During surgery, the rotation of the femoral component pinholes was recorded for all knees using PSJ and GBT and transferred to computer tomograms (CT). The rotational differences between PSJ and GBT relative to the transepicondylar axis were analysed.

RESULTS

The medium rotation of the femoral component pinholes was 1.3° ± 5.1° (min = -6.3°; max = 14.4°) for PSJ and 0.1 ± 1.4° (min = -1.6°; max = 3.4°) for GBT. Outliers of more than 3° were found more frequently with PSJ in 12 cases but only in one for GBT.

CONCLUSION

Based on our study, we would not recommend relying intra-operatively solely on the CT-based PSJ without the option to adjust or control femoral rotation.

LEVEL OF EVIDENCE

II.

Transcriptomic and proteomic insight into the effects of a defined European mistletoe extract in Ewing sarcoma cells reveals cellular stress responses

BACKGROUND

The hydrophobic triterpenes, oleanolic and betulinic acid as well as the hydrophilic mistletoe lectins and viscotoxins possess anticancer properties. They do all occur in combination in European mistletoe (Viscum album L.). Commercial Viscum album L. extracts are aqueous, excluding the insoluble triterpenes. We have previously shown that mistletoe lectins and triterpene acids are effective against Ewing sarcoma in vitro, ex vivo and in vivo.

METHODS

We recreated a total mistletoe effect (viscumTT) by combining an aqueous extract (viscum) and a triterpene extract (TT) solubilised with cyclodextrins and analysed the effects of viscumTT and the single extracts on TC-71 Ewing sarcoma cells in vitro by transcriptomic and proteomic profiling.

RESULTS

Treatment with the extracts strongly impacted Ewing sarcoma cell gene and protein expression. Apoptosis-associated and stress-activated genes were upregulated, proteasomal protein abundance enhanced and ribosomal and spliceosomal proteins downregulated. The mechanism of action of viscum, TT and viscumTT in TC-71 and MHH-ES-1 cells suggests the involvement of the unfolded protein response. While viscum and viscumTT extract treatment indicate response to oxidative stress and activation of stress-mediated MAPK signalling, TT extract treatment suggests the involvement of TLR signalling and autophagy.

CONCLUSIONS

Since the combinatory extract viscumTT exerts highly effective pro-apoptotic effects on Ewing sarcoma cells in vitro, this phytopolychemotherapy could be a promising adjuvant therapeutic option for paediatric patients with Ewing sarcoma.

Change of gait in patients with lateral osteoarthritis of the knee after mobile-bearing unicompartmental knee arthroplasty

PURPOSE

Patients with lateral osteoarthritis of the knee suffer not only from pain but also impaired gait and limited mobility. Common treatment options are total knee replacement and lateral unicompartmental knee arthroplasty (UKA). The domed lateral mobile-bearing Oxford Uni is a new treatment option for patients with isolated osteoarthritis of the lateral compartment of the knee joint. We used instrumented gait analysis and clinical scores to study patients before and after lateral UKA.

METHODS

Nineteen patients suffering from lateral osteoarthritis underwent implantation of a mobile-bearing lateral UKA. They were examined in a gait analysis before the operation and after an average follow-up time of 7 months. Gait analysis was performed on a treadmill with six infrared cameras to identify gait characteristics (e.g. velocity, stride time, stride length, knee abduction or hip adduction).

RESULTS

Mean velocity changed from 0.58 to 0.73 m/s. Significant advancements were also found in knee abduction and hip adduction. Time and length of strides improved significantly as well as the clinical scores American Knee Society Score, Oxford-12, FFb-H-OA and Devane Score.

CONCLUSION

Patients with lateral osteoarthritis of the knee showed an impaired gait with an increased knee abduction and hip adduction angle. Implantation of a lateral mobile UKA can restore normal axis of the leg and improve gait and function of the knee. Instrumented gait analysis is a suitable measuring instrument to quantify and qualify the post-operative change of gait.

LEVEL OF EVIDENCE

II.

Geographic and temporal variations in pollen exposure across Europe

BACKGROUND

The EC-funded EuroPrevall project examined the prevalence of food allergy across Europe. A well-established factor in the occurrence of food allergy is primary sensitization to pollen.

OBJECTIVE

To analyse geographic and temporal variations in pollen exposure, allowing the investigation of how these variations influence the prevalence and incidence of food allergies across Europe.

METHODS

Airborne pollen data for two decades (1990-2009) were obtained from 13 monitoring sites located as close as possible to the EuroPrevall survey centres. Start dates, intensity and duration of Betulaceae, Oleaceae, Poaceae and Asteraceae pollen seasons were examined. Mean, slope of the regression, probability level (P) and dominant taxa (%) were calculated. Trends were considered significant at P < 0.05.

RESULTS

On a European scale, Betulaceae, in particular Betula, is the most dominant pollen exposure, two folds higher than to Poaceae, and greater than five folds higher than to Oleaceae and Asteraceae. Only in Reykjavik, Madrid and Derby was Poaceae the dominant pollen, as was Oleaceae in Thessaloniki. Weed pollen (Asteraceae) was never dominant, exposure accounted for >10% of total pollen exposure only in Siauliai (Artemisia) and Legnano (Ambrosia). Consistent trends towards changing intensity or duration of exposure were not observed, possibly with the exception of (not significant) decreased exposure to Artemisia and increased exposure to Ambrosia.

CONCLUSIONS

This is the first comprehensive study quantifying exposure to the major allergenic pollen families Betulaceae, Oleaceae, Poaceae and Asteraceae across Europe. These data can now be used for studies into patterns of sensitization and allergy to pollen and foods.

Airborne olive pollen counts are not representative of exposure to the major olive allergen Ole e 1

Pollen is routinely monitored, but it is unknown whether pollen counts represent allergen exposure. We therefore simultaneously determined olive pollen and Ole e 1 in ambient air in Córdoba, Spain, and Évora, Portugal, using Hirst-type traps for pollen and high-volume cascade impactors for allergen. Pollen from different days released 12-fold different amounts of Ole e 1 per pollen (both locations P < 0.001). Average allergen release from pollen (pollen potency) was much higher in Córdoba (3.9 pg Ole e 1/pollen) than in Évora (0.8 pg Ole e 1/pollen, P = 0.004). Indeed, yearly olive pollen counts in Córdoba were 2.4 times higher than in Évora, but Ole e 1 concentrations were 7.6 times higher. When modeling the origin of the pollen, >40% of Ole e 1 exposure in Évora was explained by high-potency pollen originating from the south of Spain. Thus, olive pollen can vary substantially in allergen release, even though they are morphologically identical.

Isolation and identification of main mastitis pathogens in Mexico

The present work is a large epidemiological study aiming to detect the prevalence of subclinical mastitis and to investigate the major udder pathogens in Jalisco State, western Mexico. For this purpose, 2205 dairy cows, representing 33 Mexican dairy herds, were involved. Of 2205 cows, 752 mastitic animals were diagnosed and only 2,979 milk samples could be obtained for further investigation. All 2979 milk samples were subjected to California Mastitis Test (CMT) to differentiate clinical cases from subclinical ones where 1996 samples (67 %) reacted positively. Of these, 1087 samples (54.5%) came from cows suffering from clinical cases of mastitis. Bacteriological identification of the causative agents revealed the presence of a major group of pathogens including the Coagulase negative staphylococci (CNS), S.aureus, S.agalactiae, Corynebacterium spp. and Coliform bacteria which were detected in 464 (15.6%), 175 (5.9%), 200 (6.8%), 417 (14%) and 123 (4.1%) of the 2927 investigated quarters, 295 (15.4%), 118 (15.7%), 111 (14.8%), 227 (30.2%) and 109 (14.5%) of the 752 examined cows and in 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%) and 27 (81.8%) of the 33 herds involved, respectively. Other pathogens could be detected in the investigated milk samples such as S. dysgalactiae (0.4%), S.uberis (0.37%), Bacillus spp. (1%), Nocardia spp. (0.6%) und Candida spp. (0.1%). Meanwhile, others were present in a negligible ratio; including the Aerococcus viridans, and Enterococcus spp., Lactococcus lactis, S. bovis.

A novel triterpene extract from mistletoe induces rapid apoptosis in murine B16.F10 melanoma cells

The European mistletoe Viscum album L. is a plant used for remedies in cancer treatment. The benefit of commonly used aqueous extracts is controversial but the plant contains water insoluble triterpene acids providing interesting anticancer properties. Triterpene extracts (TE) from plants and single triterpenoids such as oleanolic acid (OA) or betulinic acid (BA) are known for their cytotoxic effects on cancer cell lines in vitro. We report here cytotoxic effects of a novel OA-rich triterpene extract from mistletoe (V. album L., Santalaceae) solubilized by 2-hydroxypropyl-β-cyclodextrin (2-HP-β-CD) on B16.F10 mouse melanoma cells. The 2-HP-β-CD solubilized triterpene extract (STE) was highly cytotoxic by causing DNA fragmentation, followed by loss of membrane integrity and intracellular adenosine-5'-triphosphate (ATP). Blocking the caspase machinery by inhibitors aborted DNA fragmentation and delayed the cytotoxic effects but did not prevent cell death. The solubilization by 2-HP-β-CD allows a solvent-free application of triterpene extracts in the in vitro setting. These findings suggest the use of STE from mistletoe as a solvent-free anticancer drug for preclinical animal experiments and clinical trials.

Psychotropic drug treatment, clinical characteristics and cognitive processing speed in patients with schizophrenia: results from the ELAN study

INTRODUCTION

Psychotropic drug combinations (PDC) are common in the treatment of patients with schizophrenia but there is little research regarding the effects of PDC on cognition.

OBJECTIVE

The aim of this study was to analyse the effects of antipsychotic monotherapy and various types of PDC on cognitive processing speed (CPS).

METHODS

ELAN is a 24-month multi-site prospective observational controlled trial following up 374 patients with schizophrenia under routine treatment conditions following discharge from inpatient treatment. The propensity score method, multinomial logistic regression analyses and mixed effects regression models were used.

RESULTS

CPS correlated significantly with PANSS and GAF scores and improved over time in the monotherapy group. Negative effects of some PDC (antipsychotics + tranquilizers/antipsychotics+at least 2 other psychopharmacological subclasses, sedative/anticholinergic drugs/high adjusted antipsychotic dose) lost significance after controlling for clinical characteristics.

DISCUSSION

Indications for PDC should be examined with care although, in the present study, effects on cognition were small.

Subintimal revascularization of chronic iliac artery occlusions using a reentry-catheter

PURPOSE

To demonstrate the value of a Reentry-Catheter for true lumen access after subintimal revascularization of chronic iliac artery occlusions.

MATERIALS AND METHODS

Subintimal revascularization was performed in 5 patients (mean age: 67 ± 12 years; female: 3, male: 2) with total iliac artery occlusion (TASC B to D), but without gaining access to the true lumen distal to the occlusion. Subsequently, a Reentry-Catheter was used to establish reentry and a new subintimal tract. Patients were followed up after 6, 12 and 24 months for clinical re-evaluation to determine the Rutherford score and the ankle brachial index (ABI). In addition, duplex ultrasound was performed to evaluate vessel patency.

RESULTS

The primary technical success rate was 100 %. In all cases angioplasty was followed by stent placement to establish the subintimal tract. The mean Rutherford score decreased from 3.6 ± 0.9 to 0.33 ± 0.57 after 24 months, while the ABI increased from 0.67 ± 0.06 to 1.2 ± 0. Vessel patency was observed in all patients available for follow-up examinations.

CONCLUSION

The Reentry-Catheter reliably allowed access to the true lumen after subintimal revascularization of occluded iliac arteries. Results in this small patient cohort showed a significant reduction in the Rutherford score, increase in the ABI, and a good patency rate after two years.

[Syphilis-associated uveitis in Switzerland]

BACKGROUND

In spite of the worldwide declining number of syphilis cases, there has been stable rate of syphilis infections in Switzerland from 2006 - 2008. In the year 2008 672 case were reported. Uveitis is the most common ocular finding in syphilis. It occurs in 2.5 %-5 % of all cases.

HISTORY AND SIGNS

Six patients (5 male, mean age 44.2 years, 1 female, age 41 year) who were examined in our facility from April 2007 to October 2009. All patients presented with posterior uveitis, with a multitude of clinical signs. All patients tested positive for syphilis-specific serologic testing (VDRL, TPPA, FTA-ABS test). One patient was initially tested negative. 5 patients showed a weakly positive VDRL and FTA-ABS test in the cerebrospinal fluid, one patient tested clearly positive.

THERAPY AND OUTCOME

5 patients were treated with i. v. penicillin G (4 Mio. units every 4 hours). Under treatment the intraocular inflammation resolved in all patients. There was a considerable rise in visual acuity for all patients.

DISCUSSION

Syphilis is a persisting problem in Switzerland. All patients belonged to a risk population. In addition 5 patients tested positive for HIV. A precise case history is therefore mandatory for an early diagnosis, that presents with diverse clinical signs. This case series shows furthermore the efficacy of the antibiotic treatment. Ophthalmologists can play an important role in the diagnosis and management of this severe disease.

Tailoring gold nanostructures for near-field optical applications

A method of combined thin-film deposition, electron beam lithography, and ion milling is presented for the fabrication of gold and silver nanostructures. The flexibility of lithographical processes for the variation of geometric parameters is combined with three-dimensional control over the surface evolution. Depending on the etching angle, different shapes ranging from cones over rods to cups can be achieved. These size- and shape-tunable structures present a toolbox for nano-optical investigations. As an example, optical properties of systematically varying structures are examined in a parabolic mirror confocal microscope.

Coating of meso-porous metallic membranes with oriented channel-like fine pores by pulsed laser deposition

There is increasing demand to functionalize meso- and nanoporous materials by coating and make the porous substrate biocompatible or environmentally friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. We adopted the pulsed laser deposition (PLD) method to coat Ni(3)Al-based meso-porous membranes, which were fabricated from a single-crystal Ni-based superalloy by a unique selective phase dissolution technique. These membranes were about 250 µm thick and had channel-like pores (∼200 nm wide) with very high aspect ratio. Two different coating materials, i.e. diamond-like carbon (DLC) and titanium, were used to coat these membranes. High energy C or Ti ions, produced in the plasma plume by the PLD process, penetrated the channel-like pores and deposited coatings on the pore walls deep inside the membrane. The thickness and the quality of coatings on the pore walls were examined using the dual-beam system. The coating thickness, of the order of 50 nm, was adherent to the pore walls and was quite uniform at different depths. The carbon and the Ti deposition behaved quite similarly. The preliminary experiments showed that the PLD is an adequate method for coating fine open cavities of complex geometry. Simulations based on stopping and the range of ions in matter (SRIM) calculations helped in understanding the deposition processes on pore walls at great depths.

AMP-activated protein kinase (AMPK) action in skeletal muscle via direct phosphorylation of PGC-1alpha

Activation of AMP-activated kinase (AMPK) in skeletal muscle increases glucose uptake, fatty acid oxidation, and mitochondrial biogenesis by increasing gene expression in these pathways. However, the transcriptional components that are directly targeted by AMPK are still elusive. The peroxisome-proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha) has emerged as a master regulator of mitochondrial biogenesis; furthermore, it has been shown that PGC-1alpha gene expression is induced by exercise and by chemical activation of AMPK in skeletal muscle. Using primary muscle cells and mice deficient in PGC-1alpha, we found that the effects of AMPK on gene expression of glucose transporter 4, mitochondrial genes, and PGC-1alpha itself are almost entirely dependent on the function of PGC-1alpha protein. Furthermore, AMPK phosphorylates PGC-1alpha directly both in vitro and in cells. These direct phosphorylations of the PGC-1alpha protein at threonine-177 and serine-538 are required for the PGC-1alpha-dependent induction of the PGC-1alpha promoter. These data indicate that AMPK phosphorylation of PGC-1alpha initiates many of the important gene regulatory functions of AMPK in skeletal muscle.

A fundamental system of cellular energy homeostasis regulated by PGC-1alpha

Maintenance of ATP levels is a critical feature of all cells. Mitochondria are responsible for most ATP synthesis in eukaryotes. We show here that mammalian cells respond to a partial chemical uncoupling of mitochondrial oxidative phosphorylation with a decrease in ATP levels, which recovers over several hours to control levels. This recovery occurs through an increased expression of the transcriptional coactivator peroxisome proliferator-activated receptor-coactivator 1alpha (PGC-1alpha) and mitochondrial genes. Cells and animals lacking PGC-1alpha lose this compensatory mechanism and cannot defend their ATP levels or increase mitochondrial gene expression in response to reduced oxidative phosphorylation. The induction of PGC-1alpha and its mitochondrial target genes is triggered by a burst of intracellular calcium, which causes an increase in cAMP-response-element-binding protein and transducer of regulated cAMP-response-element-binding proteins actions on the PGC-1alpha promoter. These data illustrate a fundamental transcriptional cycle that provides homeostatic control of cellular ATP. In light of this compensatory system that limits the toxicity of mild uncoupling, the use of chemical uncoupling of mitochondria as a means of treating obesity should be re-evaluated.

Leukemia-targeting ligands isolated from phage-display peptide libraries

Ligands specifically binding to leukemia cells may be used for drug targeting, resulting in more effective treatment with less side effects. Little is known about receptors specifically expressed on acute myeloid leukemia (AML) cells or ligands thereof. We selected random phage display peptide libraries on Kasumi-1 AML cells. A peptide with the sequence CPLDIDFYC was enriched. Phage displaying this peptide strongly bound to Kasumi-1 and SKNO-1 cells and binding could be inhibited by the cognate peptide. Both, Kasumi-1 and SKNO-1 cells carry the chromosomal translocation t(8;21), leading to aberrant expression of the fusion protein AML1/ETO. CPLDIDFYC also strongly and specifically bound primary AML1/ETO-positive AML blasts as well as U-937 cells with forced AML1/ETO expression, suggesting that the CPLDIDFYC receptor may be upregulated upon AML1/ETO expression. Gene expression profiling comparing a panel of CPLDIDFYC-binding and CPLDIDFYC-nonbinding cell lines identified a set of potential receptors for the CPLDIDFYC peptide. Further analysis suggested that alpha4beta1 integrin (VLA-4) is the CPLDIDFYC receptor. Finally, we showed that the CPLDIDFYC-phage is internalized upon receptor binding, suggesting that the CPLDIDFYC-receptor-ligand interaction may be exploitable for targeting drugs or gene therapy vectors to leukemia cells carrying the suitable receptor.

Suppression of reactive oxygen species and neurodegeneration by the PGC-1 transcriptional coactivators

PPARgamma coactivator 1alpha (PGC-1alpha) is a potent stimulator of mitochondrial biogenesis and respiration. Since the mitochondrial electron transport chain is the main producer of reactive oxygen species (ROS) in most cells, we examined the effect of PGC-1alpha on the metabolism of ROS. PGC-1alpha is coinduced with several key ROS-detoxifying enzymes upon treatment of cells with an oxidative stressor; studies with RNAi or null cells indicate that PGC-1alpha is required for the induction of many ROS-detoxifying enzymes, including GPx1 and SOD2. PGC-1alpha null mice are much more sensitive to the neurodegenerative effects of MPTP and kainic acid, oxidative stressors affecting the substantia nigra and hippocampus, respectively. Increasing PGC-1alpha levels dramatically protects neural cells in culture from oxidative-stressor-mediated death. These studies reveal that PGC-1alpha is a broad and powerful regulator of ROS metabolism, providing a potential target for the therapeutic manipulation of these important endogenous toxins.