Mena/VASP and αII-Spectrin complexes regulate cytoplasmic actin networks in cardiomyocytes and protect from conduction abnormalities and dilated cardiomyopathy

Background

In the heart, cytoplasmic actin networks are thought to have important roles in mechanical support, myofibrillogenesis, and ion channel function. However, subcellular localization of cytoplasmic actin isoforms and proteins involved in the modulation of the cytoplasmic actin networks are elusive. Mena and VASP are important regulators of actin dynamics. Due to the lethal phenotype of mice with combined deficiency in Mena and VASP, however, distinct cardiac roles of the proteins remain speculative. In the present study, we analyzed the physiological functions of Mena and VASP in the heart and also investigated the role of the proteins in the organization of cytoplasmic actin networks.

Results

We generated a mouse model, which simultaneously lacks Mena and VASP in the heart. Mena/VASP double-deficiency induced dilated cardiomyopathy and conduction abnormalities. In wild-type mice, Mena and VASP specifically interacted with a distinct αII-Spectrin splice variant (SH3i), which is in cardiomyocytes exclusively localized at Z- and intercalated discs. At Z- and intercalated discs, Mena and β-actin localized to the edges of the sarcomeres, where the thin filaments are anchored. In Mena/VASP double-deficient mice, β-actin networks were disrupted and the integrity of Z- and intercalated discs was markedly impaired.

Conclusions

Together, our data suggest that Mena, VASP, and αII-Spectrin assemble cardiac multi-protein complexes, which regulate cytoplasmic actin networks. Conversely, Mena/VASP deficiency results in disrupted β-actin assembly, Z- and intercalated disc malformation, and induces dilated cardiomyopathy and conduction abnormalities.

A Visual Analytics Approach to Multiscale Exploration of Environmental Time Series

We present a Visual Analytics approach that addresses the detection of interesting patterns in numerical time series, specifically from environmental sciences. Crucial for the detection of interesting temporal patterns are the time scale and the starting points one is looking at. Our approach makes no assumption about time scale and starting position of temporal patterns and consists of three main steps: an algorithm to compute statistical values for all possible time scales and starting positions of intervals, visual identification of potentially interesting patterns in a matrix visualization, and interactive exploration of detected patterns. We demonstrate the utility of this approach in two scientific scenarios and explain how it allowed scientists to gain new insight into the dynamics of environmental systems.

A Visual Analysis Concept for the Validation of Geoscientific Simulation Models

Geoscientific modeling and simulation helps to improve our understanding of the complex Earth system. During the modeling process, validation of the geoscientific model is an essential step. In validation, it is determined whether the model output shows sufficient agreement with observation data. Measures for this agreement are called goodness of fit. In the geosciences, analyzing the goodness of fit is challenging due to its manifold dependencies: 1) The goodness of fit depends on the model parameterization, whose precise values are not known. 2) The goodness of fit varies in space and time due to the spatio-temporal dimension of geoscientific models. 3) The significance of the goodness of fit is affected by resolution and preciseness of available observational data. 4) The correlation between goodness of fit and underlying modeled and observed values is ambiguous. In this paper, we introduce a visual analysis concept that targets these challenges in the validation of geoscientific models - specifically focusing on applications where observation data is sparse, unevenly distributed in space and time, and imprecise, which hinders a rigorous analytical approach. Our concept, developed in close cooperation with Earth system modelers, addresses the four challenges by four tailored visualization components. The tight linking of these components supports a twofold interactive drill-down in model parameter space and in the set of data samples, which facilitates the exploration of the numerous dependencies of the goodness of fit. We exemplify our visualization concept for geoscientific modeling of glacial isostatic adjustments in the last 100,000 years, validated against sea levels indicators - a prominent example for sparse and imprecise observation data. An initial use case and feedback from Earth system modelers indicate that our visualization concept is a valuable complement to the range of validation methods.

Early functional results after hemiarthroplasty for femoral neck fracture: a randomized comparison between a minimal invasive and a conventional approach

BACKGROUND

A minimal invasive approach for elective hip surgery has been implemented in our institution in the past. It is widely hypothesized that implanting artificial hips in a minimal invasive fashion decreases surgical trauma and is helpful in the rehabilitation process in elective hip surgery. Thereby geriatric patients requiring emergency hip surgery also could theoretically benefit from a procedure that involves less tissue trauma.

METHODS

Sixty patients who sustained a fractured neck of femur were randomly assigned into two groups. In the minimal invasive arm, the so called "direct anterior approach" (DAA) was chosen, in the conventional arm the Watson-Jones-Approach was used for implantation of a bipolar hemi-arthroplasty.Primary outcome parameter was the mobility as measured by the four-item-Barthel index. Secondary outcome parameters included pain, haemoglobin-levels, complications, duration of surgery, administration of blood transfusion and external length of incision. Radiographs were evaluated.

RESULTS

A statistically significant difference (p = 0,009) regarding the mobility as measured with the four-item Barthel index was found at the 5th postoperative day, favouring the DAA. Evaluation of the intensity of pain with a visual analogue scale (VAS) showed a statistically significant difference (p = 0,035) at day 16. No difference was evident in the comparison of radiographic results.

CONCLUSIONS

Comparing two different approaches to the hip joint for the implantation of a bipolar hemi-arthroplasty after fractured neck of femur, it can be stated that mobilization status is improved for the DAA compared to the WJA when measured by the four-item Barthel index, there is less pain as measured using the VAS. There is no radiographic evidence that a minimal invasive technique leads to inferior implant position.

LEVEL OF EVIDENCE

Level II therapeutic study.

Peripartum pain management in opioid dependent women

Increased pain sensitivity and the development of opioid tolerance complicate the treatment of pain experiencedby opioid maintained pregnantwomenduring delivery and the perinatal period. Theaim of the present study was to investigate differences in pain management of opioid maintained compared to nondependent pregnant women during delivery and the postpartum period. 40 deliveries of 37 opioid dependent women enrolled in a double-blind, double-dummy randomized controlled trial (RCT) examining the safety and efficacy of methadone (mean dose at the time of delivery = 63.89 mg) and buprenorphine (mean dose at the time of delivery = 14.05 mg) during pregnancy were analyzed and participants were matched to a non-dependent comparison group of 80 pregnant women. Differences in pain management (opioid and non-opioid analgesic medication) during delivery and perinatal period were analyzed. Following cesarean delivery opioid maintained women received significantly less opioid analgesics (day of delivery p = 0.038; day 1: p = 0.02), NSAIDs were administered more frequently to opioid dependent patients than to the comparison group during cesarean section and on the third day postpartum. Significantly higher nicotine consumption in the group of opioid dependentwomenhad a strong influence onthe retrieved results, and might be considered as an independent factor of altered pain experience. Differences in pain treatment became evident when comparing opioid maintained women to healthy controls. These differences might be based on psychosocial consequences of opioid addiction along with the lack of an interdisciplinary consensus on pain treatment protocols for opioid dependent patients.

Smyd2 controls cytoplasmic lysine methylation of Hsp90 and myofilament organization

Protein lysine methylation is one of the most widespread post-translational modifications in the nuclei of eukaryotic cells. Methylated lysines on histones and nonhistone proteins promote the formation of protein complexes that control gene expression and DNA replication and repair. In the cytoplasm, however, the role of lysine methylation in protein complex formation is not well established. Here we report that the cytoplasmic protein chaperone Hsp90 is methylated by the lysine methyltransferase Smyd2 in various cell types. In muscle, Hsp90 methylation contributes to the formation of a protein complex containing Smyd2, Hsp90, and the sarcomeric protein titin. Deficiency in Smyd2 results in the loss of Hsp90 methylation, impaired titin stability, and altered muscle function. Collectively, our data reveal a cytoplasmic protein network that employs lysine methylation for the maintenance and function of skeletal muscle.

Needs of fathers and mothers of schizophrenia patients

Introduction

Most studies investigating the problems and needs of schizophrenia patients’ carers include only one care-giving relative - mostly the patients’ mothers.

Purpose

The compare needs of mothers and fathers of patients with schizophrenia.

Methods

101 sets of parents of patients suffering from schizophrenia were included in this study. They were assessed by means of the “Carers’ Needs Assessment for Schizophrenia”.

Results

Compared to fathers, mothers reported significantly more often problems concerning stress due to earlier life events and burn-out. Mothers required some interventions such as individual psychoeducation or family counselling more than twice as often than fathers. Overall, mothers reported more problems and needs than fathers. The number of mothers’ problems was predicted by not living with a partner and a shorter duration of the patients’ illness (DUPI). The number of mothers’ needs was predicted by patients’ psychiatric symptoms, not living with a partner and a shorter DUPI. Among fathers we could not identify any predictors, neither for problems nor for needs.

Conclusions

Parents of schizophrenic patients have various problems handling their child's illness and therefore need professional support. Overall, mothers reported more problems and needs for interventions than fathers. The differences between mothers’ and fathers’ problems and needs indicate the importance of considering the carer's gender in clinical work.

Native GABA(B) receptors are heteromultimers with a family of auxiliary subunits

GABA(B) receptors are the G-protein-coupled receptors for gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter in the brain. They are expressed in almost all neurons of the brain, where they regulate synaptic transmission and signal propagation by controlling the activity of voltage-gated calcium (Ca(v)) and inward-rectifier potassium (K(ir)) channels. Molecular cloning revealed that functional GABA(B) receptors are formed by the heteromeric assembly of GABA(B1) with GABA(B2) subunits. However, cloned GABA(B(1,2)) receptors failed to reproduce the functional diversity observed with native GABA(B) receptors. Here we show by functional proteomics that GABA(B) receptors in the brain are high-molecular-mass complexes of GABA(B1), GABA(B2) and members of a subfamily of the KCTD (potassium channel tetramerization domain-containing) proteins. KCTD proteins 8, 12, 12b and 16 show distinct expression profiles in the brain and associate tightly with the carboxy terminus of GABA(B2) as tetramers. This co-assembly changes the properties of the GABA(B(1,2)) core receptor: the KCTD proteins increase agonist potency and markedly alter the G-protein signalling of the receptors by accelerating onset and promoting desensitization in a KCTD-subtype-specific manner. Taken together, our results establish the KCTD proteins as auxiliary subunits of GABA(B) receptors that determine the pharmacology and kinetics of the receptor response.

Hook plate for medial clavicle fracture

Medial clavicle fractures are the least common type of clavicular fractures. Although rare, such injuries deserve rapid diagnosis and effective treatment to avoid future complications. An optimal, standardized operative treatment has not been yet established. We report a case of medial clavicle fracture, where primary operative treatment was indicated due to gross dislocation. An open reduction and osteosynthesis with a modified hook plate was performed, leading to an excellent postoperative outcome after a sixteen-month follow-up. The hook plate seems to be a promising approach for the operative treatment of medial clavicle fractures.

Deltoid muscular flap transfer for the treatment of irreparable rotator cuff tears

The purpose of this study was to evaluate the outcome of deltoid muscle flap transfer for the treatment of irreparable rotator cuff tears. In a retrospective study 20 consecutive patients were evaluated. The index procedure took place between 2000 and 2003. Fifteen patients were male, mean age was 62 years. Inclusion criterion was a rotator cuff defect Bateman grade IV. Exclusion criteria were smaller defects, shoulder instability and fractures of the injured shoulder. An open reconstruction with acromioplasty and a pedicled delta flap was performed. Follow up period was mean 42 months. Follow-up included clinical examination, Magnetic Resonance Imaging (MRI) and the Constant and Simple (CS) shoulder tests. According to the Constant shoulder test the results were good in 13 patients, fair in 5 and unsatisfactory in 2. The pre-operative Constant Score improved from mean 25.7 points (±5.3) to 72.3 (±7.8) at follow-up. The mean values for the subcategories of CS increased significantly from 3.9 to 14.4 points for pain and from 4.2 to 15.9 points for activities daily routine (p<0.05). The change in range of motion and strength were not significant (p>0.05). Results of the Simple Shoulder Test showed a significant increase of the mean values from pre-operative 4.3 to 14.7 points post-operatively. MRI showed a subacromial covering of the defect in all cases, all flaps where intact on MRI but always the flap showed marked fatty degeneration. In conclusion, the delta flap is a simple method for the repair of large defects of the rotator cuff leading to satisfying medium results.

Sensitivity of crescent-shaped metal nanoparticles to attachment of dielectric colloids

The response of the plasmonic resonances of crescent-shaped nanoparticles to the attachment of a dielectric colloidal particle was investigated. The colloid serves as a model analyte which is easy to handle and allows for benchmarking of the sensing capabilities of plasmonic resonators. A clear red shift of the resonances is observed in agreement with the prediction from numerical simulations. From the response for different colloid positions, we obtain information on the nanoscale near field distribution. A field localization to length scales of 20 nm is proven directly. All resonators under study show a comparable response which is important for possible sensing application. We estimate that a further increase of the sensitivity by a factor of 8 would allow for label-free single biomolecule detection.

Fathers and Mothers of Patients with Schizophrenia

Aims:

To investigate caregiving and its consequences among fathers and mothers of the same patients suffering from schizophrenia.

Methods:

101 patients as well as both parents were investigated using the “Carers' Needs Assessment for Schizophrenia”, the “Beck Depression Inventory”, the “Involvement Evaluation Questionnaire” and the “Family Problem Questionnaire”.

Results:

The mean number of days fathers lived together with the patients was not significant from that of the mothers, but the average duration (hours per week) of contact with the patient was significantly higher for mothers than for fathers. Among 40% of the sample, fathers and mothers spend an equal amount of time caring for the patient. Mothers reported significantly more often problems than fathers concerning stress due to earlier life events and burn-out. Mothers needed some interventions such as individual psychoeducation or family counselling more than twice as often as fathers. Mothers reported overall higher numbers of problems and needs for intervention than fathers. The overall score of caregivers' involvement did not differ significantly between fathers and mothers. The mothers' objective burden was significantly higher than the fathers' objective burden, but parents did not show differences concerning subjective burden. Using the “Beck Depression Inventory”, mothers were more often depressed than fathers.

Conclusions:

This study shows that often fathers and mothers spend an equal amount of time caring for the patient. The differences found between mothers and fathers should be considered when planning services for family caregivers.

Disability in Schizophrenic Disorders

Aims:

The purpose of this study was to investigate disability among patients suffering from schizophrenia and to identify predictors of disability.

Methods:

101 patients from different types of psychiatric services in Vienna and diagnosed with schizophrenia according to ICD-10 were included. They were investigates by means of 36-Item self-administered version of the WHO Disability Assessment Schedule II (WHO-DAS-II) and the PANSS-scale. Patients’ mothers and fathers were asked to fill in the Family Problem Questionnaire.

Results:

The mean total score of the WHO-DAS-II was 74.1 (SD 21.9). When using weighted sub-scores the highest disability scores were found for social contacts, participation in society and household (means 2.58, 2.57 and 2.51 respectively). Using logistic regression, overall disability was positively associated with patient's age, overall severity of symptoms (PANSS) and number of previous hospital admissions. Overall disability was not associated with duration of illness and or patient's gender. The subjective burden experienced by patients’ fathers and mothers were increased by reduced social contacts and impaired participation in society, while we could not find an association with other domains of patient's disability (understanding, mobility, self-care, household).

Conclusions:

This study shows that schizophrenia results in disability in several domains. Family caregivers’ burden was predominantly increased by social consequences of schizophrenia.

Pharmacophilia and pharmacophobia: determinants of patients' attitudes towards antipsychotic medication

OBJECTIVE

To identify factors that influence attitudes towards psychopharmacological treatment in patients suffering from schizophrenia and schizoaffective psychoses.

METHODS

Ninety-two participants in an outpatient psychoeducational program, classed as "pharmacophobic" or "pharmacophilic" according to the Drug Attitude Inventory scale, were compared with regard to sociodemographic variables, clinical characteristics, subjective deficit syndrome, illness concepts, knowledge, locus of control, and quality of life.

RESULTS

The 59 pharmacophilic and the 33 pharmacophobic patients did not differ significantly with regard to most sociodemographic variables, symptoms, or classic personality traits such as locus of control, self-concept, and quality of life. The only differences concerned hospitalization history ( P < 0.05) and statements on the actual, subjective experience of desired and undesired effects of medication ( P < 0.01).

CONCLUSIONS

The impact of subjective experiences with drug treatment on attitudes towards medication and compliance needs to be a main focus of interventions targeting attitudes towards pharmacological treatment.

DaVinci robotic-assisted laparoscopic bariatric surgery: is it justified in a routine setting?

BACKGROUND

Laparoscopic silicone adjustable gastric banding (SAGB) has gained popularity for the surgical treatment of morbid obesity. The implantable gastric stimulator (IGS) system represents a novel surgical alternative. We aimed to assess the feasibility of robotic-assisted laparoscopic bariatric operations and to critically elucidate the technical and financial advantages and patient outcome.

METHODS

Robotic-assisted laparoscopic bariatric procedures were performed on 10 consecutive patients using the daVinci robot system (4 SAGB, 4 IGS, 2 SAGB revisions). 10 conventional laparoscopic-operated patients (4 SAGB, 4 IGS, 2 SAGB revisions) during the learning curve served as controls. Equipment, operative technique and procedural time were evaluated. A cost analysis was calculated.

RESULTS

The personnel equipment, numbers of trocars and operation technique were comparable in both groups. The mean operative time was 137 min (range 110-175) and 97 min (60-140) in robotic-assisted and conventional laparoscopy, respectively (P =0.04). Establishment of the pneumoperitoneum and placement of trocars and robotic arms took a mean of 30 min (15-45) in the robotic-assisted group, compared with 5 min in the control group (P <0.001). In 1 patient, intraoperative gastric injury was suspected and led to band removal in the robotic-assisted group. There was no postoperative complication. Average procedural costs were significantly higher in the robotic-assisted group.

CONCLUSION

Primary and revisional robotic-assisted bariatric surgery is technically simple, with the benefit of precise instrument handling. However, it is still expensive, the set-up of the system is time-consuming, and a limited variety of instruments are available presently.

High-dose tamoxifen and sulindac as first-line treatment for desmoid tumors

BACKGROUND

Desmoid tumors are mesenchymal nonmetastasizing neoplasms. Although rare in the general population, they are a common extracolonic manifestation of familial adenomatous polyposis (FAP). Because of high tumor recurrence rates, surgery has been less than satisfactory in the treatment of desmoid tumors. In the current study, high doses of tamoxifen in combination with sulindac were used to treat severe desmoid tumors to avoid surgery.

METHODS

Since 1992, 25 patients at Heinrich Heine University (Dusseldorf, Germany) were treated with a combination of tamoxifen and sulindac. In the current study, 17 patients with FAP-associated and 8 patients with sporadic desmoid tumors received 120 mg of tamoxifen and 300 mg of sulindac daily. Every 6 months, the protracted course of desmoid growth was measured by computed tomography and/or magnetic resonance imaging scans. Tumor responses were characterized as progressive disease, stable disease (SD), partial regression (PR), and complete regression (CR).

RESULTS

Of the group of patients who received tamoxifen and sulindac as a primary treatment, all three patients with sporadic desmoid tumors demonstrated cessation of growth, and 10 of the 13 patients with FAP-associated tumors achieved either a PR or CR. In the sporadic desmoid tumor group, eight of nine patients developed tumor recurrences after undergoing surgery at other institutions. Of these, two patients had SD and two patients had a PR to CR.

CONCLUSIONS

The patients with desmoid tumors who were managed conservatively with high-dose tamoxifen and sulindac had the best outcome. Desmoid tumor recurrence after surgery was high and in the FAP-associated tumor group, therapy with tamoxifen and sulindac was found to be less successful. Based on this experience, the authors recommended high-dose tamoxifen and sulindac as the primary treatment for patients with FAP-associated desmoid tumors. However, to our knowledge, the best approach after surgical intervention for patients with sporadic desmoid tumors remains to be determined.

[Psychooncological aspects in the care of females in HNPCC families]

HNPCC families are characterized by a genetic predisposition for colorectal and other cancers. In Düsseldorf we pursue an interdisciplinary counselling approach (geneticists, psychologists and surgeons). Apart from the genetic counselling itself, special emphasis is placed on the benefits of surveillance and screening recommendations. In this pilot study we were interested in investigating if the counselled women had understood the increased risk of gynecological cancers and correspondingly underwent the intensified screening modalities. We selected the approach of a telefone interview and encountered broad acceptance for contacting persons this way. Affected women are better compliant to screening recommendations than women at risk. Both groups consider colonoscopy more strainful than gynecological surveillance. A regular transvaginal ultrasound is not performed in some 40 % of at risk women although 2/3 of them see their gynecologist in regular intervals. Given the support of gynecologists a higher rate of transvaginal ultrasound in women at risk should be achievable.

Identification and quantification of phosphatidylethanolamine-derived glucosylamines and aminoketoses from human erythrocytes--influence of glycation products on lipid peroxidation

While the Maillard reaction of amino acids and proteins as well as its consequences in vivo has been thoroughly investigated, little attention has so far been paid to the glycation of aminophospholipids such as phosphatidylethanolamine (PE) or phosphatidylserine (PS), which are essential for structure and functionality of biological membranes. PE-derived glucosylamines (Schiff-PEs) and aminoketoses (Amadori-PEs) have now for the first time been simultaneously identified and quantified in erythrocytes from diabetics and healthy individuals by liquid chromatography-electrospray mass spectrometry (LC-(ESI)MS). The amounts of glycated PE (gPE) were significantly higher in diabetics (0.18-34.2 mol% Schiff-PE and 0.047-0.375 mol% Amadori-PE) than in controls (0.12-3.99 mol% Schiff-PE and 0.018-0.055 mol% Amadori-PE). A positive correlation between fructosylated hemoglobin (HbA(1c)) and the gPE levels was established. No advanced glycation endproducts (AGEs) like 5-hydroxymethylpyrrole-2-carbaldehyde (pyrrole-PE), carboxymethyl (CM-PE), or carboxyethyl (CE-PE) derivatives were detected. To investigate the influence of gPE on lipid peroxidation of biological membranes, liposomes consisting of soy-PE and synthetically prepared Amadori-PE (16:0-16:0) were incubated for several days and the formation of oxidation products was monitored. It could be shown that Amadori-PE extensively promotes lipid peroxidation even in the absence of transition metal ions like Cu(2+) and Fe(3+). Oxidative damage to membrane lipids therefore is supposed to be at least partially caused by the glycation of aminophospholipids.

Neopterin: a prognostic variable in operations for lung cancer

BACKGROUND

We studied the prognostic value of preoperatively measured neopterin to predict survival of lung cancer patients. Neopterin is produced and secreted by interferon-gamma-stimulated monocytic cells. High urinary neopterin concentrations are found in patients with viral infections, allograft rejection episodes, and some malignant diseases. In various tumor types high urinary neopterin concentrations are associated with a worse prognosis.

METHODS

Preoperative neopterin levels of 110 patients (29 women, 81 men) with lung cancer including 7 patients with small cell lung cancer were measured and related to the time of survival after operation. Patients with clinically suspected stage IIIB lung cancer were not operated and therefore not enrolled in this study. Infectious diseases were not apparent at the time of preoperative urine sampling. Median postoperative follow-up period was 17.4 months.

RESULTS

In a univariate analysis, patients with a preoperative neopterin concentration of more than 212 micromol/mol creatinine (4th quartile) were determined to have a significantly lower survival probability. In a multivariate analysis, a neopterin concentration of more than 212 micromol/mol creatinine (p < 0.01) and T-stage status (p < 0.005) were determined to be significantly predictive variables for worse survival prognosis.

CONCLUSIONS

Preoperative neopterin proved to be a reliable prognostic factor for survival. Immunology may provide an accurate assessment of tumor aggression and its clinical behavior. In this sense, neopterin can serve as an immunologically based estimation of malignant outgrowth. In patients who are operable by clinical tumor stage but have a high risk for operation, elevated preoperative neopterin may help in the decision for a nonoperative treatment.