Ferromagnetic coupling of mononuclear Fe centers in a self-assembled metal-organic network on Au(111)

The magnetic state and magnetic coupling of individual atoms in nanoscale structures relies on a delicate balance between different interactions with the atomic-scale surroundings. Using scanning tunneling microscopy, we resolve the self-assembled formation of highly ordered bilayer structures of Fe atoms and organic linker molecules (T4PT) when deposited on a Au(111) surface. The Fe atoms are encaged in a three-dimensional coordination motif by three T4PT molecules in the surface plane and an additional T4PT unit on top. Within this crystal field, the Fe atoms retain a magnetic ground state with easy-axis anisotropy, as evidenced by x-ray absorption spectroscopy and x-ray magnetic circular dichroism. The magnetization curves reveal the existence of ferromagnetic coupling between the Fe centers.

NCB-plating in the treatment of geriatric and periprosthetic femoral fractures

BACKGROUND

The aim of this study is the presentation of the polyaxial locking NCB-plate in the treatment of femoral fractures, especially in elderly patients and in proximity of a prosthetic implant. The reduction and fixation of these fractures is a challenging surgical procedure with high complication rates reported up to 40%.

PATIENTS AND METHODS

A total of 72 patients with femoral fractures had polyaxial locking plate osteosynthesis. Indications included fractures of the shaft and around an implant. Concerning surgical procedures, three different standardized techniques were performed: (1) minimally invasive with percutaneous distal insertion using a targeting device; (2) mini-open with additional cerclage wire via the same approach and (3) a conventional open reduction and internal fixation. Data collection included intraoperative data and early complications at 6, 24 and 52 weeks. Fifty-two patients had an implant or prosthesis in situ. Thirty-three patients were treated by technique (1), 32 patients had mini-open surgery and seven patients conventional open surgery.

RESULTS

Thirty-nine patients attended clinical follow-up after 52 weeks. Twenty-two patients were interviewed by telephone, two were untraceable and nine patients had died. Bony consolidation without secondary loss of reduction was confirmed after 52 weeks in all patients but two. Plate breakage occurred in these two at 25 and 31 weeks after surgery due to non-union. Implant related complications (17% in total) lead to surgical revision in five other cases: two deep wound infections as well as three minor revisions. When itemizing complications according to surgical technique used, most major complications occurred following open surgery.

CONCLUSION

The availability of polyaxial locking implants widened the range of indications for plate fixation in femoral fractures. The advantages of the polyaxial locking implant combined with minimally invasive surgical technique contribute to successful management of this population category. Early revision rate is noticeably lower compared to similar procedures.

LEVEL OF EVIDENCE

IV retrospective series.

[Revenue and losses with vertebral augmentation under the G-DRG system 2012 - a comparison of supply costs in the context of vertebroplasty and kyphoplasty]

BACKGROUND

If clearly indicated and implemented, augmentations of vertebral bodies with cement are standardized, safe and low-risk procedures. However, the multiplicity of providers and systems are today more varied than ever. At present, the systems differ starkly from one another not only in specifications, possible applications and extensions of indications, but they are also extremely variable in price. Publications have shown that in times of medical-economic change, vertebral augmentations make sense not only medically, but also in terms of economics and the national economy. Our analysis targets the question of how insurance costs with vertebroplasty and kyphoplasty affect profit margins per G-DRG (German Diagnosis Related Groups) in consideration of the different system approaches of the providers.

MATERIALS AND METHODS

After reviewing the literature, extremely varied, minimally invasive augmentation methods and techniques for treating vertebral body fractures were identified and classified. These were grouped based also [sic: on] OPS and possibly further subdivisions. Material costs were gathered based on average price quotations of different providers and techniques and aligned with those from the literature. The inpatient costs per day were estimated as a lump sum according to published information, since our analysis was interested in less detailed process costs as these are difficult to transfer to other clinics due to parameters being unique to each facility. The G-DRGs concerned were likewise determined according to the case-based lump sum catalogue from 2012. Based on this, the material costs as well as the daily costs per day of inpatient stay according to the average length of stay per G-DRG were subtracted.

RESULTS

Vertebral augmentation methods are classified into vertebroplasty and kyphoplasty according to OPS. In addition, according to current literature, a further subdivision of kyphoplasty into substance-conserving or direct cement injection techniques and substance-destroying or indirect cement injection techniques took place. The procedures involve material costs between 10-40 % of G-DRG revenue. The profit margin of vertebral augmentation ranges from approx. 4100 € to approx. 11 400 €. The calculative costs of the inpatient care per day amount to 488.86 €. Based on the average lengths of stay per G-DRG (7.8-12.6 days) for 2012 determined by the InEK (Institut für das Entgeltsystem im Krankenhaus [Institute for the Hospital Remuneration System]), the financial costs of inpatient care were calculated between 3813.11 € and 6159.65 €. A shortfall of -197.53 € for the treatment of a vertebral body resulted for the vertebroplasty. This shortfall increases with the treatment of three vertebral bodies and a PCCL = 4 to -466.30 €. The indirect cement injection techniques accounted for a positive profit margin of 196.03 € for the treatment of a vertebra. Due to high material costs, however, this dips into the negative in the amount of -1227.70 € for two vertebrae and increases to -2522.50 € for the treatment of three vertebral bodies. In contrast, the multilevel care in substance-preserving kyphoplasty techniques show a positive profit margin of 72.30 € for the treatment of two vertebrae and 577.50 € for the treatment of three vertebrae.

CONCLUSION

Against the background of the increasing economization of the health care system, it should be emphasized once more that the decision for a therapy or a system based on medical reasons should only be made by the treating physician. The vertebroplasty could not be performed at a profit in our analysis, despite comparatively low material costs. A shortfall between -197.53 € and -466.30 € was determined. The comparatively higher material costs of the kyphoplasty make comparisons important. The results of our investigation also show that supposedly inexpensive purchases of materials are not automatically a favorable alternative. In addition, the kyphoplasty techniques currently available on the market are not necessarily comparable. According to our investigation, profits of between 196.03 € and 577.50 € are to be realized in the selection of vertebral augmentation systems based on purely economic considerations. The results of our analysis show that the pure comparison of figures of the average material costs of a G-DRG and the material price distort the picture. A calculation of the profit margin on the basis of costs of care per vertebral body is more definitive.

[Reimbursement for kyphoplasty in the Germann diagnosis-related groups system 2011/2012. Material costs versus treatment costs]

BACKGROUND

The treatment of osteoporotic vertebral fractures by means of kyphoplasty is an accepted and safe procedure.

AIM

In Germany the reimbursement for kyphoplasty and vertebroplasty differs greatly. The growing diversity of suppliers and systems makes a comparison possible and necessary. Besides the illustration of kyphoplasty in the German diagnosis-related group (G-DRG) system and the amendments for 2012 we analyzed the procedures and associated costs.

METHOD

Using the example of two manufacturers and different system approaches, both of which can be charged as kyphoplasty, we try to point out the importance of selecting exact comparison parameters. In particular material and treatment costs are compared for both methods.

Switching the electronic properties of Co-octaethylporphyrin molecules on oxygen-covered Ni films by NO adsorption

Using x-ray absorption spectroscopy, we demonstrate that the electronic properties of Co-octaethylporphyrin (CoOEP) molecules on oxygen-covered ultrathin Ni films can be reversibly manipulated by a chemical stimulus. This is achieved by adsorption of nitrogen monoxide (NO), leading to the formation of a NO-CoOEP nitrosyl complex, and subsequent thermal desorption of the NO from the Co ions. The integration of the absorption spectra of the Co L(2,3) edges reveals a partial oxidation of the Co ions after dosing with NO compared to the pristine sample, for which a valency of 2+ and a low-spin state of the Co ions can be deduced from the Co L(2,3) XAS line shape. By means of x-ray magnetic circular dichroism the magnetic moments of the Co ions were found to be coupled parallel to the magnetization of the Ni films across the intermediate layer of atomic oxygen, before and after NO uptake.

Detection of Shiga toxin-producing Escherichia coli by sandwich enzyme-linked immunosorbent assay using chicken egg yolk IgY antibodies

Enterohemorrhagic Escherichia coli (EHEC), a subset of Shiga toxin producing E. coli (STEC) is associated with a spectrum of diseases that includes diarrhea, hemorrhagic colitis and a life-threatening hemolytic-uremic syndrome (HUS). Regardless of serotype, Shiga toxins (Stx1 and/or Stx2) are uniformly expressed by all EHEC, and so exploitable targets for laboratory diagnosis of these pathogens. In this study, a sandwich ELISA for determination of Shiga toxin (Stx) was developed using anti-Stx2B subunit antibodies and its performance was compared with that of the Vero cell assay and a commercial immunoassay kit. Chicken IgY was used as capture antibody and a HRP-conjugated rabbit IgG as the detection antibody. The anti-Stx2B IgY was harvested from eggs laid by hens immunized with a recombinant protein fragment. Several parameters were tested in order to optimize the sandwich ELISA assay, including concentration of antibodies, type and concentration of blocking agent, and incubation temperatures. Supernatants from 42 STEC strains of different serotypes and stx variants, including stx_2EDL933, stx_2vha, stx_2vhb, stx_2g, stx_1EDL933, and stx_1d were tested. All Stx variants were detected by the sandwich ELISA, with a detection limit of 115 ng/ml Stx2. Twenty three strains negative for stx genes, including different bacteria species, showed no activity in Vero cell assay and produced negative results in ELISA, except for two strains. Our results show that anti-Stx2B IgY sandwich ELISA could be used in routine diagnosis as a rapid, specific and economic method for detection of Shiga toxin-producing E. coli.

Nitrotyrosine and nitrate/nitrite levels in cardiac arrest survivors treated with endovascular hypothermia

The protective effect of therapeutic hypothermia in cardiac arrest survivors (CAS) has been previously well documented. Animal studies have indicated that attenuation of tissue oxidative stress (OS) may be involved in the mechanisms that lead to the beneficial effect of hypothermia. The extent of OS and nitric oxide (NO) production in adult CAS treated with endovascular hypothermia is, however, unknown. A total of 11 adult patients who experienced cardiac arrest out of hospital were included in the present study, and all were treated with mild hypothermia using the Thermogard XP (Alsius, USA) endovascular system. A target core temperature of 33 °C was maintained for 24 hours, with a subsequent rewarming rate of 0.15 °C per hour, followed by normothermia at 36.8 °C. Blood samples for the measurement of nitrotyrosine and nitrate/nitrite levels were drawn at admission and every 6 hours thereafter for two days. During the hypothermic period, the levels of nitrotyrosine and nitrates/nitrites were comparable with baseline values. During the rewarming period, serum levels of both parameters gradually increased and, during the normothermic period, the levels were significantly higher compared with hypothermic levels (nitrotyrosine, P<0.001; nitrates/nitrites, P<0.05). In our study, significantly lower levels of nitrotyrosine and nitrates/nitrites were demonstrated during hypothermia compared with levels during the normothermic period in adult CAS. These data suggest that attenuation of OS and NO production may be involved in the protective effect of hypothermia in adult CAS.

[Allergic reactions as differential diagnosis for periprosthetic infection]

Metallic orthopedic devices are composed of elements known to be skin sensitizers in the general population and metal-on-metal hip prostheses in particular have the theoretical advantage of producing less abrasive wear than metal-on-polyethylene prostheses. However, there is concern about the possibility of hypersensitivity reactions with typical elicitors, such as nickel, chromium or cobalt. These materials are also used for total knee arthroplasty (TKA) and may elicit an immune response the role of which is still unclear in the outcome of arthroplasty. The immune response is dominated by perivascular T and B lymphocyte tissue infiltration around the hip replacement. The infiltrates are mostly surrounded by so-called high endothelial venules. This reaction is associated with periprosthetic osteolysis and aseptic loosening of the prostheses. The differentiation of hypersensitivity and low-grade infection is initially a diagnosis by exclusion using aspiration cultures. The final diagnosis is only resolved by histological investigation of synovial tissue. A close cooperation between orthopedic surgeons, pathologists and microbiologists is necessary to diagnose specific cellular differences in hypersensitivity and infection in tissue investigations.

Dermal penetration of creatine from a face-care formulation containing creatine, guarana and glycerol is linked to effective antiwrinkle and antisagging efficacy in male subjects

BACKGROUND

  The dermal extracellular matrix provides stability and structure to the skin. With increasing age, however, its major component collagen is subject to degeneration, resulting in a gradual decline in skin elasticity and progression of wrinkle formation. Previous studies suggest that the reduction in cellular energy contributes to the diminished synthesis of cutaneous collagen during aging.

AIMS

  To investigate the potential of topically applied creatine to improve the clinical signs of skin aging by stimulating dermal collagen synthesis in vitro and in vivo.

PATIENTS/METHODS

  Penetration experiments were performed with a pig skin ex vivo model. Effects of creatine on dermal collagen gene expression and procollagen synthesis were studied in vitro using cultured fibroblast-populated collagen gels. In a single-center, controlled study, 43 male Caucasians applied a face-care formulation containing creatine, guarana extract, and glycerol to determine its influence on facial topometric features.

RESULTS

  Cultured human dermal fibroblasts supplemented with creatine displayed a stimulation of collagen synthesis relative to untreated control cells both on the gene expression and at the protein level. In skin penetration experiments, topically applied creatine rapidly reached the dermis. In addition, topical in vivo application of a creatine-containing formulation for 6 weeks significantly reduced the sagging cheek intensity in the jowl area as compared to baseline. This result was confirmed by clinical live scoring, which also demonstrated a significant reduction in crow's feet wrinkles and wrinkles under the eyes.

CONCLUSIONS

  In summary, creatine represents a beneficial active ingredient for topical use in the prevention and treatment of human skin aging.

The hormone melatonin stimulates renoprotective effects of "early outgrowth" endothelial progenitor cells in acute ischemic kidney injury

Endothelial progenitor cells (EPCs) protect the kidney from acute ischemic injury. The aim of this study was to analyze whether pretreatment of murine "early outgrowth" EPCs (eEPCs) with the hormone melatonin increases the cells' renoprotective effects in the setting of murine acute ischemic renal failure. Male (8-12 wk old) C57Bl/6N mice were subjected to unilateral ischemia-reperfusion injury postuninephrectomy (40 min). Postischemic animals were injected with either 0.5×10(6) untreated syngeneic murine eEPCs or with cells, pretreated with melatonin for 1 h. Injections were performed shortly after reperfusion of the kidney. While animals injected with untreated cells developed acute renal failure, eEPC pretreatment with melatonin dramatically improved renoprotective actions of the cells. These effects were completely reversed after cell pretreatment with melatonin and the MT-1/-2 antagonist luzindole. In vitro analysis revealed that melatonin reduced the amount of tumor growth factor-β-induced eEPC apoptosis/necrosis. Secretion of vascular endothelial growth factor by the cells was markedly stimulated by the hormone. In addition, migratory activity of eEPCs was enhanced by melatonin and supernatant from melatonin-treated eEPCs stimulated migration of cultured mature endothelial cells. In summary, melatonin was identified as a new agonist of eEPCs in acute ischemic kidney injury.

The sandflies (Diptera: Psychodidae, Phlebotominae) in military camps in northern Afghanistan (2007-2009), as identified by morphology and DNA 'barcoding'

As part of a continuous, standardized programme of monitoring the Leishmania vectors in German military camps in northern Afghanistan between 2007 and 2009, a detailed taxonomic analysis of the endemic sandfly fauna, as sampled using light and odour-baited traps, was conducted. Of the 10 sandfly species that were recorded, six may serve as enzootic and/or zooanthroponotic vectors of parasites causing human leishmaniasis. The use of a simple DNA-'barcoding' technique based on the mitochondrial cyt b gene, to identify the collected sandflies to species level, revealed (1) a clear discrimination between the potential vector species, (2) clustering of species within most subgenera, and (3) particularly high heterogeneity within the subgenus Paraphlebotomus (Phlebotomus alexandri being grouped with Ph. papatasi rather than with other Paraphlebotomus species). The data also indicate a high level of genetic heterogeneity within the subgenus Sergentomyia but close similarity between Sergentomyia sintoni and Sergentomyia murgabiensis. The morphological similarity of many medically important sandflies can make species identification difficult, if not impossible. The new DNA-barcoding techniques may provide powerful discriminatory tools in the future.

Surgical dislocation of the hip for the fixation of acetabular fractures

Surgical dislocation of the hip in the treatment of acetabular fractures allows the femoral head to be safely displaced from the acetabulum. This permits full intra-articular acetabular and femoral inspection for the evaluation and potential treatment of cartilage lesions of the labrum and femoral head, reduction of the fracture under direct vision and avoidance of intra-articular penetration with hardware. We report 60 patients with selected types of acetabular fracture who were treated using this approach. Six were lost to follow-up and the remaining 54 were available for clinical and radiological review at a mean follow-up of 4.4 years (2 to 9).

Substantial damage to the intra-articular cartilage was found in the anteromedial portion of the femoral head and the posterosuperior aspect of the acetabulum. Labral lesions were predominantly seen in the posterior acetabular area. Anatomical reduction was achieved in 50 hips (93%) which was considerably higher than that seen in previous reports. There were no cases of avascular necrosis. Four patients subsequently required total hip replacement. Good or excellent results were achieved in 44 hips (81.5%). The cumulative eight-year survivorship was 89.0% (95% confidence interval 84.5 to 94.1). Significant predictors of poor outcome were involvement of the acetabular dome and lesions of the femoral cartilage greater than grade 2. The functional mid-term results were better than those of previous reports.

Surgical dislocation of the hip allows accurate reduction and a predictable mid-term outcome in the management of these difficult injuries without the risk of the development of avascular necrosis.

[Two-photon microscopy of the cornea using intrinsic contrast]

BACKGROUND

Three-dimensional imaging of the cornea under physiological conditions is best performed with intrinsic contrast mechanisms for the visualisation of cells and extracellular matrix. However, the unique transparency of the cornea goes along with a lack of contrast for the extracellular matrix (ECM) in reflective mode microscopy and optical coherence tomography.

METHODS

Femtosecond laser-based non-linear microscopy provides novel contrast mechanisms for the visualisation of ECM. The confinement of the non-linear contrast to the focus volume provides an intrinsic sectioning property for 3D imaging. Further advantages of the infrared light are lower phototoxicity and higher penetration depth into the tissue. For the visualisation of the cornea and its layered substructures two non-linear contrast mechanisms are of main interest: Two-photon excited autofluorescence of NAD(P)H in the cytoplasma and second harmonic generation (SHG) in the collagen-I fibres of the stroma. Ex-vivo corneas of the rabbit were imaged to demonstrate the abilities of non-linear microscopy.

RESULTS

Using the autofluorescence of NAD(P)H the corneal epithelium with squamous cells, wing cells and basal cells is visualised in three dimensions without additional exogenoeus staining. Stromal keratocytes are also imaged using the NAD(P)H autofluoresecence. The layered structure of lamella in the stroma is visible after virtual resclicing of the 3D volume data. The en-face SHG images detected through the transparent cornea in forward direction show areas of parallel streaks, which increase in size and periodically alter in orientation (90 degrees , 45 degrees) with increasing depth from anterior to posterior. These streaks are not visible in the backward SHG signal. First results on rabbit corneas, which were cross-linked with Rivoflavin and UV application showed a signature of treatment five weeks post treatment. There were zones in the stroma totally lacking NAD(P)H autofluorescence and the abundance of keratocytes was less homogeneous than in control corneas.

CONCLUSION

These results and current reports on applications in the literature show that femtosecond laser-based non-linear microscopy is an emerging imaging modality which provides dye-free imaging of the corneal ECM and therefore complements scattering imaging modalities such as optical coherence tomography and confocal laser scanning microscopy in the reflective mode.

[Virtual endoscopy of the nose and paranasal sinuses in real-time. Surgical planning system "Sinus endoscopy" (SPS-SE)]

PROBLEM

The aim of this study was the development and clinical evaluation of a new method for virtual endoscopy of the nose and paranasal sinuses.

MATERIAL AND METHODS

The surgical planning system "sinus endoscopy" (SPS-SE) was completely newly developed. The surfaces of the CT images are represented with direct volume rendering (raycasting) which allows a sufficiently high image repetition frequency with the movement of the virtual endoscopy and material effects for a natural appearance were added. Detail accuracy of the virtual illustrations was examined with the help of a picture-statistic comparison between optical and the virtual endoscopy. The evaluation of the system by the patients and physicians was made with a validated questionnaire.

RESULTS

The deviations from defined landmarks of virtual in comparison to optical endoscopy are between 1.4 mm and 11.1 mm. Manoeuvering the virtual endoscope was found to be better than with the optical endoscope but the important parameters for visualization were similar. The accuracy of volume rendering, the high variability of scaling of the anatomical borders and orientation were judged to be negative factors. Altogether there was a balanced opinion from the ENT surgeons but without exception patients judged the system positively.

DISCUSSION

This investigation proved the efficiency of SPS-SE for three-dimensional real time reconstruction of high-resolution CT data of the nose and paranasal sinuses. However, some modifications are necessary before introduction into routine use.

[Teaching non-technical skills for critical incidents: Crisis resource management training for medical students]

BACKGROUND

Physicians have to demonstrate non-technical skills, such as communication and team leading skills, while coping with critical incidents. These skills are not taught during medical education. A crisis resource management (CRM) training was established for 4th to 6th year medical students using a full-scale simulator mannikin (Emergency Care Simulator, ECS, METI).

PATIENTS AND METHODS

The learning objectives of the course were defined according to the key points of Gaba's CRM concept. The training consisted of theoretical and practical parts (3 simulation scenarios with debriefing). Students' self-assessment before and after the training provided the data for evaluation of the training outcome.

RESULTS

A total of 65 students took part in the training. The course was well received in terms of overall course quality, debriefings and didactic presentation, the mean overall mark being 1.4 (1: best, 6: worst). After the course students felt significantly more confident when facing incidents in clinical practice. The main learning objectives were achieved.

CONCLUSION

The effectiveness of applying the widely used ECS full-scale simulator in interdisciplinary teaching has been demonstrated. The training exposes students to crisis resource management issues and motivates them to develop non-technical skills.

Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

Reduced tumour cell proliferation and delayed development of high-grade mammary carcinomas in cathepsin B-deficient mice

Expression levels of the papain-like cysteine protease cathepsin B (Ctsb) have been positively correlated with mammary tumour progression and metastasis; however, its roles in the hallmark processes of malignant growth remain poorly defined. Using Ctsb-deficient mice we investigated tumour cell differentiation, proliferation and apoptosis in the Tg(MMTV-PyMT) mouse mammary cancer model. Absence of Ctsb significantly impaired development of high-grade invasive ductal carcinomas and reduced the metastatic burden in the lungs. Mice lacking Ctsb exhibited reduced cell proliferation in mammary carcinomas and their lung metastases. Notably, intravenous injection of primarily isolated, Ctsb-expressing tumour cells into congenic Ctsb-deficient mice revealed impaired cell proliferation in the resulting experimental lung metastases, providing evidence for the involvement of Ctsb in paracrine regulation of cancer cell proliferation. No Ctsb genotype-dependent difference in tumour cell death was observed in vivo or by treatment of isolated PyMT cancer cells with tumour necrosis factor-alpha. However, cancer cells lacking Ctsb exhibited significantly higher resistance to apoptosis induction by the lysosomotropic agent Leu-Leu-OMe. Thus, our results indicate an in vivo role for Ctsb in promoting cellular anaplasia in mammary cancers and proliferation in lung metastases.

[Anti-metastatic effects of serine protease inhibitors: animal models for analysis]

To date, no effective adjuvant drug preventing the aggressive spread of tumour cells in late stages of cancer disease or at the time-point of primary tumour removal is available. Although proteases, including members of the large serine protease family, were shown to be promising targets for an anti-metastatic cancer therapy, synthetic protease inhibitors (SPIs) have so far failed to be introduced into the clinic. In addition to considerations in the design of classical in vivo -tests of SPIs as cancer therapy agents, we here review our findings with a straightforward, highly sensitive and very fast in vivo metastasis model and its implications in the development of efficient anti-metastatic SPIs. The lacZ-tagging of tumour cells of this very aggressive T-cell lymphoma model allowed highly sensitive and reproducible detection of metastases within seven days after tumour cell inoculation by X-gal staining of whole organs, allowing cost-effective and material-saving side-by-side screening of a series of SPIs with different specificities for different serine proteases. By establishment of specificity/antimetastatic efficacy correlations we identified coagulation factor Xa as one important target of anti-metastatic SPIs and could use this information for the subsequent design and optimization of factor Xa-specific lead structures.

CONCLUSION

We exemplify the usefulness of high-throughput in vivo analysis to direct optimization of lead structures and how this may allow unexpected insight into the molecular biology of metastasis.

Sterol composition of freshwater algivorous ciliates does not resemble dietary composition

Algivorous ciliates represent an important link in freshwater food webs, as they transfer energy and biochemical matter from their algal prey to mesozooplankton predators. However, it is still unknown how dietary composition influences the biochemical composition of ciliates. We analyzed the sterol composition of the algivorous ciliates Balanion planctonicum and Urotricha farcta and compared it to the sterol composition of their diet--the cryptomonad Cryptomonas phaseolus. The sterol composition of the ciliates did not resemble that of their algal diet. Ergosterol [(22E)-ergosta-5,7,22-trien-3beta-ol] was the sterol in highest concentration in C. phaseolus, whereas stigmasterol [(24S)-24-ethylcholesta-5,22E-dien-3beta-ol] was dominant in both B. planctonicum and U. farcta. Moreover, the occasionally higher sterol concentrations in the ciliates than in their algal diet suggest sterol accumulation by the ciliates. We conclude that dietary sterol composition influences the composition of the two algivorous ciliates studied, but species-specific differences in metabolism probably determine the ultimate sterol composition of the ciliates.

Antimetastatische Effizienz synthetischer Serinproteaseinhibitoren

Es gibt kein wirksames adjuvantes Therapeutikum, das die aggressive Ausbreitung von Tumorzellen in fortgeschrittenen Tumorstadien oder bei chirurgischer Entfernung des Primärtumors verhindert. Obwohl Proteasen einschließlich der Serinproteasen als vielversprechende Zielstrukturen für eine antimetastatische Krebstherapie ausgewiesen wurden, schlug die klinische Einführung synthetischer Proteaseinhibitoren (SPIs) fehl. Zusätzlich zu Überlegungen zu klassischen Herangehensweisen bei der Prüfung von SPIs als Krebstherapeutika in vivo, beleuchten wir hier unsere Ergebnisse mit einem einfach handhabbaren, hochsensitiven und schnellen In-vivo-Metastasierungsmodell und seine Bedeutung für die Entwicklung effizienter, antimetastatisch wirksamer SPIs. Die lacZ-Markierung sehr aggressiver T-Zell-Lymphomzellen ermöglicht die hochsensitive und reproduzierbare Detektion von Metastasen innerhalb von sieben Tagen nach Tumorzellinokulation, durch X-Gal-Färbung ganzer Organe. Dieses Modell erlaubt ein kostengünstiges und materialsparendes paralleles Screening einer Serie von SPIs mit unterschiedlichen Spezifitäten für verschiedene Serinproteasen. Durch Korrelationen zwischen Spezifität und antimetastatischer Effizienz identifizierten wir den Gerinnungsfaktor Xa als wichtige Zielstruktur antimetastatischer SPIs und konnten diese Information für das weitere Design und die Optimierung von Faktor-Xaspezifischen Leitstrukturen verwenden. Schlussfolgerung: Wir können exemplarisch zeigen, dass In-vivo-Analysen mit hohem Durchsatz die Optimierung von Leitstrukturen dirigieren können und darüber hinaus zu unerwarteten, neuen Einblicken in die Molekularbiologie der Metastasierung führen.

Cementless hemiarthroplasty in femoral neck fractures: evaluation of clinical results and measurement of migration by EBRA-FCA

Aim of the present study was to evaluate migration rates of cementless primary hemiarthroplasty in acute femoral neck fractures. In a longitudinal, prospective study 46 patients were treated by cementless hemiarthroplasty. Clinical follow up was correlated with the EBRA-FCA method. In 30% of all patients stem migration amounted to more than 2 mm; further, these patients were seen to have a high level of activity. A high degree of migration in more than 30% of all patients requires critical scepticism toward further use of the investigated cementless stem as hemiarthroplasty. According to literature, migration of more than 2 mm suggests a high probability of early aseptic loosening. In patients with a low degree of activity good results could be observed; nevertheless, in patients with a high level of activity the combination of the investigated cementless stem with a solid fracture head cannot be recommended.

Do predictive mechanisms improve the angular vestibulo-ocular reflex in vestibular neuritis?

Recovery from vestibular neuritis (VN) is often incomplete which leads to persistent vestibular imbalance during rapid head movements. Patients with unilateral vestibular lesions have a larger gain of the horizontal vestibulo-ocular reflex during active compared to passive head movements. To test whether this gain increase is related to predictive mechanisms we studied 15 patients with VN and 14 control subjects during predictable and unpredictable passive horizontal head impulses in the light and darkness. The vestibulo-ocular reflex showed a significantly shorter latency and higher gain in the light for predictable head impulses towards the ipsilesional side. However, this effect is small and might contribute but cannot exclusively account for the gain increase during active head movements.

Rat enamel contains RP59: a new context for a protein from osteogenic and haematopoietic precursor cells

We have recently identified a protein, RP59, in bone marrow cells and young osteoblasts, in cells involved in bone repair and in young erythroblasts and megakaryocytes. Here, we report immunohistochemical data at the light- and electron-microscope level indicating that RP59 is also present in newly secreted tooth enamel of the rat and in ameloblasts, the formative cells. In enamel matrix, RP59 was located proximal to secretory ameloblasts only, i.e. in newly secreted material. Distal enamel and enamel in association with maturation stage ameloblasts were unlabelled. Secretory ameloblasts contained RP59 in the matrix-proximal region including Tomes' processes, post-secretory ameloblasts in the cell-matrix interface. Western blotting of proteins from tooth germs identified RP59 as a band at 90 kD, co-migrating with RP59 from bone marrow and spleen. Antisera versus a chemically synthesised RP59 peptide and versus a bacteria-synthesised protein fragment reacted in the same manner. In situ hybridisation of tooth tissue revealed RP59 RNA specifically in ameloblasts. The reverse transcription/polymerase chain reaction method identified tooth RNA coding for RP59. Sequence analysis indicated that RP59 RNA from tooth and marrow had the same sequence. An internal sequence motif was found in rat RP59 resembling a signal implicated in secretion of the chicken "engrailed" gene product. The findings indicate that RP59 is a genuine product of ameloblasts and that it is secreted in the course of enamel formation together with other matrix components.

[AWMF-guideline: cocaine-, amphetamine-, ecstasy- and hallucinogen-related disorders]

Actually, guidelines for treatment of substance-related disorders were written under the overall control of the DG-Sucht e. V. and the DGPPN e. V. This appears within the framework of the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaft (AWMF). The leading objective of these guidelines is the description of the current scientifically proven and evidence-based medicine in addiction to derive recommendations to therapy. In this context, the guideline for treatment of cocaine-, amphetamine-, ecstasy-, and halluzinogen-related disorders is introduced.

[Differences between anteroposterior and posterior spondylodesis in clinical scores]

The present study on spondylitis patients was carried out to compare prospectively results of clinical scores of patients treated with anteroposterior or anterior spondylodesis. A total of 22 patients with spondylitis were enrolled in the randomized trial to undergo an operation with anteroposterior or posterior spondylodesis. For quality of life adjustment, the SF-36 health survey was applied. Pain and disability were measured using the Oswestry low-back pain disability questionnaire and visual analogue scales (VAS). Twelve patients were assigned to undergo anteroposterior spondylodesis and ten patients anterior spondylodesis. Postoperative improvement of spinal function, general health, well being, back pain, and mobility could be observed in both groups of patients. Better results of patients treated with anterior spondylodesis compared with anteroposterior spondylodesis were seen. No statistical difference was found between the two groups at any time. The less invasive nature of anterior spondylodesis could be responsible for that result.Anterior spondylodesis should used if possible and deemed adequate because it causes less discomfort.