Dehydroepiandrosterone reduces expression of glycolytic and gluconeogenic enzymes in the liver of male and female rats

The in vivo effect of dehydroepiandrosterone (DHEA) on hepatic glycogen content and on glucose metabolizing enzymes was investigated in male and female Sprague-Dawley rats treated with 0.6% (w/w) DHEA in the diet for 3, 7, 14, 28 and 140 days. The glycolytic enzymes studied (glucokinase, hexokinase, pyruvate kinase) showed a significant persistent decrease in activity in both sexes after 3-7 days of treatment. Gluconeogenic enzymes (glucose-6-phosphatase, fructose-1,6-bisphosphatase) were increased after 3 days, but decreased after 7-14 days. Glycolytic enzymes showed a stronger reduction than gluconeogenic enzymes. Females were slightly more affected than males. Glucose-6-phosphate dehydrogenase was unchanged in females, but increased in males. Glycogen content and the activity of glycogen phosphorylase were reduced after 3 days of treatment. mRNA analysis of glucokinase and phosphorylase indicated that these enzyme alterations were accompanied by reduced transcriptional expression, while glucose-6-phosphate dehydrogenase mRNA levels were unchanged. Withdrawal of DHEA from 4 week-treated rats was associated with an almost complete reversibility of the enzyme alterations after 2 weeks. After long-term treatment (140 days) glucokinase, glucose-6-phosphatase and fructose-1,6-bisphosphatase activities were no longer altered. Since DHEA treatment affects the key enzymes of glucose metabolic pathways in the same sense, it is suggested that DHEA does not regulate individual enzymes but rather common regulatory factors or signalling pathways.

The use of Endurant stent-graft for abdominal aortic aneurysm: the story about extension of instruction for use with persistent good results of stent-graft latest generation

The Endurant stent-graft (Medtronic, Inc., Minneapolis, MN, USA) is a latest generation device for the treatment of abdominal aortic aneurysm. The idea behind designing such a graft came from the intention to broad the instruction for use (IFU) and to enable it to treat more challenging anatomy including the 10mm neck lengths, and more severe suprarenal and infrarenal angulations. Endurant stent-graft has active fixation through suprarenal stent with anchoring pins to provide migration resistance, optimized heights of stents and spacing between them for improved flexibility and conformability, low-profile delivery system with hydrophilic coating and controlled simple deployment mechanism. Short term results are excellent. Technical and clinical success is confirmed in Regulatory trials (EU and USA), as well as in ENGAGE and the Canadian registry. Many current publications record the use of Endurant stent-graft outside the Instruction for use. The results in a group of patients outside the instruction for use are comparable to those within instruction for use; with the exception of perioperative proximal endoleak type I. Mid-term results are consistent with short-term results. The long-term results are lacking.

Hypericin for visualization of high grade gliomas: first clinical experience

AIMS

We aimed to demonstrate that Hypericin, a component of St. Johns Wort, selectively visualizes malignant gliomas. Hypericin is known as one of the most powerful photosensitizers in nature with excellent fluorescent properties.

METHODS

In five patients with a recurrence of a malignant glioma a newly developed water soluble formulation of hypericin was given intravenously (0.1 mg/kg body weight) 6 h before the surgical procedure. Tumor resection was performed under white light and fluorescence mode. The intensity grade of the tissue fluorescence was categorisized by the surgeon in three grades, highly fluorescent, weakly fluorescent and not fluorescent. In these areas tissue samples were taken and investigated by two blinded independent neuropathologists. Tissue samples were histologically classified differentiating between tumor tissue, tumor necrosis, tissue with scattered tumor cells and normal brain tissue.

RESULTS

In all patients tumor tissue was clearly distinguishable by its typically red fluorescence color from normal brain tissue which was colored blue under a special fluorescent filter. Histological evaluation of the 110 tissue samples showed a specificity of 100% and sensitivity of 91% for one of the two neuropathologists, whereas specificity for second pathologist was 90% and sensitivity 94%. The i.v. application of Hypericin proofed to be safe in all cases and there were no side effects observed.

CONCLUSION

Hypericin in its water soluble form is a well tolerated drug. In addition to its high photosensitizing properties hypericin will open up interesting new therapeutic possibilities especially when used in combination with fluorescence detection and simultaneously photodynamic therapy.

Mental contrasting of a dieting wish improves self-reported health behaviour

Mentally contrasting a desired future with present reality standing in its way promotes commitment to feasible goals, whereas mentally indulging in a desired future does not. Dieting students (N = 134) reported their most important dieting wish that they deemed attainable within a 2-week period. Then, they were directed to mentally contrast or indulge in thoughts and images about the named dieting wish. A control condition was given no directions. Two weeks after the experiment, dieters retrospectively rated their behaviour change: in the mental contrasting condition they reported having eaten relatively fewer calories overall, fewer high-calorie food and more low-calorie food compared to those in the indulging and control conditions, and they also reported having been more physically active. This transfer effect from one health domain to another suggests a more generalised effect of mental contrasting versus indulging and control than previously assumed.

Patterned self-assembly of gold nanoparticles on chemical templates fabricated by soft UV nanoimprint lithography

Chemical templates for the patterned immobilization of gold nanoparticles were fabricated by soft UV nanoimprint lithography. The template structures were fabricated by means of the consecutively performed process steps of nanoimprint lithography, reactive ion etching, chemical functionalization with amino groups, and lift-off of imprint resist. These chemical templates were used for the defined assembly of 20 nm diameter citrate stabilized gold nanoparticles from aqueous solution. By reducing the ionic strength of the solution, one- and zero-dimensional particle assemblies were generated on sub-100-nm template structures. By this means, the pattern resolution predefined by the lithography process could be easily enhanced by dilution of the nanoparticle solution.

Induction of luciferase activity under the control of an hsp70 promoter using high-intensity focused ultrasound: combination of bioluminescence and MRI imaging in three different tumour models

The in vivo temporal changes of luciferase activity were investigated under the control of an hsp70 promoter in three tumour models after the application of different intensities of high-intensity focused ultrasound (HIFU). Three cell lines, SCCVII, NIH3T3 and M21 were stably transfected with a plasmid containing the hsp70 promoter and luciferase reporter gene, and tumours were subcutaneously initiated into mice. At a size of 1300 ± 234 mm(3), the tumours were exposed to five intensities of continuous HIFU (802-1401-2157-3067-4133 W/cm(2)) for 20 sec. Bioluminescence and MR imaging were performed to assess luciferase activity and signal intensity changes in the tissue. The MRI scan protocol was pre- and post-contrast T1-wt-SE, T2-wt-FSE, DCE-MRI, diffusion-wt STEAM sequence, T2 relaxation time determination obtained on a 1.5-T GE MRI scanner. The NIH3T3 tumours showed the highest luciferase activity of 328.1 ± 7.1 fold at 24 h at a HIFU intensity of 3067 W/cm(2), the M21 tumours of 3.2 ± 0.6 fold 8 hours and the SCCVII tumours 2.9 ± 0.9 fold 4 hours post-HIFU at 2157 W/cm(2). The greatest increase in T2 signal intensity and T2 relaxation time of 20.7 ± 3.4% was seen in the SCCVII tumours. The highest contrast medium uptake of 10.1 ± 1.1% was noted in the M21 tumours, and 14.8 ± 1.9% in the SCCVII tumours. In all tumours, a significant increase in the diffusion coefficient was seen with increased HIFU intensity, the highest of which was 40.3 ± 4.1% in the SCCVII tumours. The three tumour cell lines stably transfected with the hsp70/luciferase gene showed differential luciferase activity, which peaked at different times after the application of HIFU and was dependant on tumour type and HIFU energy deposition.

Evidence that venous hypertension causes stasis dermatitis

A clinical model to examine the hypothesis that venous hypertension of the lower leg per se can cause lower leg stasis dermatitis is described. To prove this concept, we retrospectively studied a consecutive series of 38 patients with lower leg dermatitis who underwent phlebological examination at our consultation over a period of four years. Among those patients who had an insufficiency of the superficial veins only, without insufficiency of the deep veins, 22 had undergone patch testing to common allergens in phlebology. We found 10 patients with a stasis dermatitis of the lower leg and an incompetent great saphenous vein, six of whom had no detectable contact sensitization at all and another four exclusively to phlebologically irrelevant substances, e.g. nickel, cobalt, chromate or epoxid resin. All these 10 patients showed long saphenous vein incompetence from the groin to the medial aspect of the leg. All were operated by classical flush ligation and saphenectomy. Lower leg dermatitis healed in all 10 patients within 8–12 weeks and no recurrence was observed (1 year follow-up). These results support clinical experience that venous hypertension alone indeed can cause lower leg dermatitis.

[Recommendations for the use of polyhexanide-containing products for the treatment of wounds]

Polihexanide-containing wound products are often used for the treatment of acute and chronic wounds. Although information pertaining to the use of polihexanide can be found in the literature, the appropriate use of these products in clinical practice is not always clear. The goal of this short review is to provide clinically relevant recommendations to physicians and nurses treating patients with acute and chronic wounds. This review describes the clinically relevant characteristics of polihexanide and gives recommendations for the prophylaxis and treatment of wound infections.

[Chronic venous insufficiency in postthrombotic syndrome and varicose veins]

Venous disorders have a high prevalence and require approximately 1% of health budgets of industrialized countries. The postthrombotic syndrome (PTS) is defined by subjective symptoms and morphologic trophical skin changes following deep venous thrombosis. Prevention of venous thromboembolism in risk situations, easy availability of diagnostic tools (D-dimers, colour-coded duplex sonography) and early detection of deep venous thrombosis, as well as immediate therapeutic anticoagulation along with leg compression during the acute phase and over a two year period of time significantly reduce the incidence of PTS. Chronic venous insufficiency (CVI) includes trophical skin and soft tissue pathologies of the lower leg due to venous hypertension in the distal venous system of the lower extremity. Roughly, two main causes can be distinguished. (A) Deep venous insufficiency (A1 in postthrombotic syndrome; A2 in primary deep venous insufficiency) and (B) superficial venous reflux, usually varicose veins. Compression therapy, surgical ablation of superficial venous reflux, and tangential ablation with split skin graft (shave treatment) of refractory venous ulcers are the mainstays in the treatment of CVI.

Current reversals and synchronization in coupled ratchets

Current reversal is an intriguing phenomenon that has been central to recent experimental and theoretical investigations of transport based on ratchet mechanism. By considering a system of two interacting ratchets, we demonstrate how the coupling can be used to control the reversals. In particular, we find that current reversal that exists in a single driven ratchet system can ultimately be eliminated with the presence of a second ratchet. For specific coupling strengths a current-reversal free regime has been detected. Furthermore, in the fully synchronized state characterized by the coupling threshold k(th), a specific driving amplitude a(opt) is found for which the transport is optimum.

Abdominal compartment syndrome

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are frequently encountered in critically ill patients and carry a high morbidity and mortality risk. Despite these facts, IAH/ACS are still overlooked by many physicians and therefore timely diagnosis is not made and treatment is often inadequate. All clinicians should be aware of the risk factors predicting IAH/ACS, the profound implications and derangements on all organ systems, the clinical presentation, the appropriate measurement of intra-abdominal pressure to detect IAH/ACS and the current treatment options for these detrimental syndromes. This comprehensive review provides knowledge about known facts, unresolved issues and future directions for research to improve patient survival and long-term outcome.

[A rare interstitital lung disease in two smokers]

Pulmonary Langerhans-cell histiocytosis should be suspected in patients with nodular or cystic changes in the upper pulmonary lobes. Patients with Langerhans-cell histiocytosis usually have a history of smoking; lack of nicotine exposure or an age over 60 years makes the diagnosis unlikely. The diagnostic work-up should include a high-resolution CT of the chest as well as a bronchoalveolar lavage, bronchoscopic and/or surgical lung biopsy. Smoking cessation is the essential part of the treatment.

Responding to patient safety incidents: the "seven pillars"

BACKGROUND

Although acknowledged to be an ethical imperative for providers, disclosure following patient safety incidents remains the exception. The appropriate response to a patient safety incident and the disclosure of medical errors are neither easy nor obvious. An inadequate response to patient harm or an inappropriate disclosure may frustrate practitioners, dent their professional reputation, and alienate patients.

METHODS

The authors have presented a descriptive study on the comprehensive process for responding to patient safety incidents, including the disclosure of medical errors adopted at a large, urban tertiary care centre in the United States.

RESULTS

In the first two years post-implementation, the "seven pillars" process has led to more than 2,000 incident reports annually, prompted more than 100 investigations with root cause analysis, translated into close to 200 system improvements and served as the foundation of almost 106 disclosure conversations and 20 full disclosures of inappropriate or unreasonable care causing harm to patients.

CONCLUSIONS

Adopting a policy of transparency represents a major shift in organisational focus and may take several years to implement. In our experience, the ability to rapidly learn from, respond to, and modify practices based on investigation to improve the safety and quality of patient care is grounded in transparency.