Nep1-like proteins as a target for plant pathogen control

The lack of efficient methods to control the major diseases of crops most important to agriculture leads to huge economic losses and seriously threatens global food security. Many of the most important microbial plant pathogens, including bacteria, fungi, and oomycetes, secrete necrosis- and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs), which critically contribute to the virulence and spread of the disease. NLPs are cytotoxic to eudicot plants, as they disturb the plant plasma membrane by binding to specific plant membrane sphingolipid receptors. Their pivotal role in plant infection and broad taxonomic distribution makes NLPs a promising target for the development of novel phytopharmaceutical compounds. To identify compounds that bind to NLPs from the oomycetes Pythium aphanidermatum and Phytophthora parasitica, a library of 587 small molecules, most of which are commercially unavailable, was screened by surface plasmon resonance. Importantly, compounds that exhibited the highest affinity to NLPs were also found to inhibit NLP-mediated necrosis in tobacco leaves and Phytophthora infestans growth on potato leaves. Saturation transfer difference-nuclear magnetic resonance and molecular modelling of the most promising compound, anthranilic acid derivative, confirmed stable binding to the NLP protein, which resulted in decreased necrotic activity and reduced ion leakage from tobacco leaves. We, therefore, confirmed that NLPs are an appealing target for the development of novel phytopharmaceutical agents and strategies, which aim to directly interfere with the function of these major microbial virulence factors. The compounds identified in this study represent lead structures for further optimization and antimicrobial product development.

Is shortening of Tibialis Anterior in addition to calf muscle lengthening required to improve the active dorsal extension of the ankle joint in patients with Cerebral Palsy?

INTRODUCTION

Shortening of the tibialis anterior tendon (TATS) has been shown to improve the ankle dorsiflexion in swing following the calf muscle lengthening procedure (CMLP) in patients with cerebral palsy (CP). Others have reported the similar improvements following CMLP but without TATS. However there are no studies comparing both procedures. Therefore the purpose of the study was to compare the ankle dorsiflexion in swing and foot position in the sagittal plane during gait following TATS and CMLP to that of CMLP alone.

MATERIALS AND METHODS

A retrospective study was carried out in CP patients who presented with fixed equinus deformity. They were grouped into unilateral CP and bilateral CP. Depending on the procedures, each group was again subdivided into subgroup CMLP only and subgroup CMLP and TATS (CMLPTATS). All patients were subjected to pre and postoperative clinical and gait analysis.

RESULTS

44 feet in 44 patients were included in the study. Of these, 24 feet (24 patients) belonged to unilateral and 20 feet (20 patients) to bilateral CP group. The mean age of the patients at surgery was 11.5 years (6.0 - 29.0) in the unilateral CP group and 10.5 years (5.0-34.0) in the bilateral CP group. In the unilateral CP group, 12 feet belonged to subgroup CMLP and 12 to subgroup CMLPTATS with a mean equinus contracture of 7.5° in both subgroups. In bilateral CP group, 11 feet belonged to subgroup CMLP with a mean equinus contracture of 5° and 9 to subgroup CMLPTATS, with a mean equinus contracture of 10°. The subgroups did not vary significantly in the demographics, anthropometry, kinematics and kinetics of ankle joint preoperatively. The mean follow up time was 19.7 months. The surgery produced significant changes in both groups and subgroups. However, none of the relevant gait parameters were significantly different between groups and subgroups.

SIGNIFICANCE

Adding TATS to CMLP, compared to CMLP alone did not improve ankle dorsiflexion in swing and the foot position more than CMLP alone.

[Surgical management of ankylosing spondylitis (Bechterew's disease)]

Ankylosing spondylitis is an inflammatory rheumatic disease that is often associated with back pain and restricted spinal movement. In the later stages of the disease, complete ossification of the entire spine and severe deformity can occur, often resulting in a marked reduction in quality of life and an increased risk of loss of independence due to diminished visual field. Patients with ankylosing spondylitis are at greater risk of spinal fractures. These are generally complex fractures associated with high morbidity and mortality; in addition, neurological deficits are not unusual. Conventional radiological diagnosis is often insufficient to establish a diagnosis. Conservative treatment of fractures of the spine in this patient group is unsatisfactory. Surgical procedures, if necessary combined with decompression, are often the preferred treatment of choice in the fractured or malaligned ankylosed spine. Rebalancing of the sagittal profile with normalization of the visual axis and an improvement of quality of life is achieved through corrective osteotomies. Despite the high rate of complications, long-term results following spinal surgery in patients with ankylosing spondylitis are good. Minimally invasive surgery is appropriate for a further reduction in the complication rate. Meticulous preoperative planning is essential in the treatment of patients with ankylosing spondylitis.

Eudicot plant-specific sphingolipids determine host selectivity of microbial NLP cytolysins

Necrosis and ethylene-inducing peptide 1-like (NLP) proteins constitute a superfamily of proteins produced by plant pathogenic bacteria, fungi, and oomycetes. Many NLPs are cytotoxins that facilitate microbial infection of eudicot, but not of monocot plants. Here, we report glycosylinositol phosphorylceramide (GIPC) sphingolipids as NLP toxin receptors. Plant mutants with altered GIPC composition were more resistant to NLP toxins. Binding studies and x-ray crystallography showed that NLPs form complexes with terminal monomeric hexose moieties of GIPCs that result in conformational changes within the toxin. Insensitivity to NLP cytolysins of monocot plants may be explained by the length of the GIPC head group and the architecture of the NLP sugar-binding site. We unveil early steps in NLP cytolysin action that determine plant clade-specific toxin selectivity.

[Hyaluronic acid gels for pressure regulation in glaucoma treatment]

BACKGROUND

The increasing numbers of glaucoma patients and complications occuring during treatment, such as restenosis and hypotony, require new treatment options to prevent blindness in patients. Therefore, the abovementioned problems should be solved to prolong the lifetime of implants and to prevent repeated surgery.

OBJECTIVE

Can a novel stent with hyaluronic acid hydrogels (HA gel) as a functional unit be used to regulate pressure in glaucoma therapy in the long term?

MATERIAL AND METHODS

Model stents were filled with HA gels and it was investigated if these could regulate the pressure and what the underlying mechanism is.

RESULTS

The results of the investigations showed that the HA gel inside the stent functions as a pressure valve. Under certain equilibrium pressures the HA gel closes the stent and therefore retains the fluid. At a certain overpressure the HA gel enables the fluid to be released and leads to a self-regulated adjustment of the equilibrium pressure.

DISCUSSION

The next step will involve miniaturization of the stents. Experiments will then show if the valve function will also work in the dimensions necessary for an eye implant and if the current problem of hypotension in glaucoma therapy can be solved.

Management of Severe Equinovalgus in Patients With Cerebral Palsy by Naviculectomy in Combination With Midfoot Arthrodesis

BACKGROUND

Equinovalgus deformity is the second most common deformity in cerebral palsy and may be flexible or rigid. Several operative methods from joint sparing to arthrodesis have been described with varying success rates. The aim of this study was to investigate the effectiveness of naviculectomy in combination with midfoot arthrodesis (talo-cuneiform and calcaneocuboid arthrodesis) in the correction of a rigid equinovalgus foot deformity in cerebral palsy.

METHODS

Forty-eight rigid equinovalgus feet were operated upon in 30 patients from 2008 to 2013. Of these, 44 feet in 26 patients with cerebral palsy (Gross Motor Function Classification System III, IV, or V) with follow-up of more than 2 years were included in the study. The mean age at surgery was 18.1 years. The outcomes were measured objectively using radiographic angles and subjectively using 5 questions to be answered by the caregiver. The feet were then graded into excellent, good, fair, and poor. The mean follow-up was 5.0 ± 1.7 years.

RESULTS

Excellent to good results were obtained in 81% of the feet. Both objective and subjective outcomes improved significantly postoperatively ( P < .001). Three feet in 2 patients were graded as poor and underwent a revision operation for pain and recurrence.

CONCLUSIONS

Naviculectomy in combination with midfoot arthrodesis enabled a good 3-dimensional correction of the forefoot. However, the procedure did not necessarily correct the fixed subtalar joint deformity. Several additional bony and soft-tissue procedures were necessary to achieve a complete correction in these difficult feet.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Biomimetic optimisation of branched fibre-reinforced composites in engineering by detailed analyses of biological concept generators

The aim of this study is the biomimetic optimisation of branched fibre-reinforced composites based on the detailed analysis of biological concept generators. The methods include analyses of the functional morphology and biomechanics of arborescent monocotyledons and columnar cacti as well as measurements and modelling of mechanical properties of biomimetic fibre-reinforced composites. The key results show evidence of notch stress reduction by optimised stem-branch-attachment morphology in monocotyledons and columnar cacti. It could be shown that some of these highly interesting properties can be transferred into biomimetic fibre-reinforced composites.

[The Effect of Intraoperative Screw Monitoring (Root Monitoring) with the INS-1 System (NUVASIVE) on the Radiological Outcome of Dorsal Instrumentation of the Lumbar Spine]

INTRODUCTION

Transpedicular screw fixation of spinal segments has been described for a variety of surgical indications and is a key element in spinal surgery. The aim of transpedicular screw fixation is to achieve maximal stability. Screw malposition should be obviated to avoid neurological complications. There are published methods of applying evoked EMG to control screw position in relation to neural structures. These studies demonstrated that an intact bony pedicle wall acts as an electrical isolator between the screw and spinal nerve root. The aim of our study was to evaluate the impact of intraoperative pedicle screw monitoring on screw positioning.

MATERIAL AND METHODS

We enrolled 22 patients in this prospective randomised study, who underwent spinal instrumentation after being split into two equal groups. In the first group, dorsal instrumentation was supplemented with intraoperative nerve root monitoring using the INS-1-System (NuVasive, San Diego USA). In the second group, screws were inserted without additional pedicle monitoring. All patients underwent monosegmental instrumentation with "free hand implanted" pedicle screws. 44 screws were inserted in each group. The screw position was evaluated postoperatively using CT scans. The position of the screws in relation to the pedicle was measured in three different planes: sagittal, axial and coronal. The accuracy of the screw position was described using the Berlemann classification system. Screw position is classified in three groups: type 1 correct screw position, type 2 encroachment on the inner cortical wall, type 3 pedicle cortical perforation. Screw angulation and secondary operative criteria were also evaluated.

RESULTS

The use of neuromonitoring did not influence the distance between the centre of the screws and the pedicle wall. Distances only depended on the implantation side (right and left) and the height of implantation (caudal or cranial screw). Because of the low number of cases, no conclusion could be reached about the influence of root monitoring on the correct positioning of the screws. There was at least a non-significant trend towards more frequent perforation of the pedicle in the monitor group. In the present study, we showed that root monitoring had a significant effect on the scattering of transversal angles. These were increased compared to the control group. Otherwise, the implantation angle was not shown to depend on the use of neuromonitoring. Neuromonitoring did not influence blood loss or operative time.

DISCUSSION

The data did not permit any conclusion as to whether this technique can minimise the frequency of pedicle screw malposition. The four coronal plane distances did not depend on the use of neuromonitoring. The inclination angle was also unaffected by neuromonitoring. The only parameter for which we found any effect was the transverse angle. The mean values were similar in both groups, but the variances were not equal. The effect of monitoring on the only parameter which could not be evaluated by fluoroscopy is thus rather unfavourable.

An RLP23-SOBIR1-BAK1 complex mediates NLP-triggered immunity

Plants and animals employ innate immune systems to cope with microbial infection. Pattern-triggered immunity relies on the recognition of microbe-derived patterns by pattern recognition receptors (PRRs). Necrosis and ethylene-inducing peptide 1-like proteins (NLPs) constitute plant immunogenic patterns that are unique, as these proteins are produced by multiple prokaryotic (bacterial) and eukaryotic (fungal, oomycete) species. Here we show that the leucine-rich repeat receptor protein (LRR-RP) RLP23 binds in vivo to a conserved 20-amino-acid fragment found in most NLPs (nlp20), thereby mediating immune activation in Arabidopsis thaliana. RLP23 forms a constitutive, ligand-independent complex with the LRR receptor kinase (LRR-RK) SOBIR1 (Suppressor of Brassinosteroid insensitive 1 (BRI1)-associated kinase (BAK1)-interacting receptor kinase 1), and recruits a second LRR-RK, BAK1, into a tripartite complex upon ligand binding. Stable, ectopic expression of RLP23 in potato (Solanum tuberosum) confers nlp20 pattern recognition and enhanced immunity to destructive oomycete and fungal plant pathogens, such as Phytophthora infestans and Sclerotinia sclerotiorum. PRRs that recognize widespread microbial patterns might be particularly suited for engineering immunity in crop plants.

[Simultaneous thoracoscopically assisted anterior release in prone position and posterior scoliosis correction : What are the limits?]

BACKGROUND

In spite of modern pedicle-based systems, the correction of a rigid rib hump or hypokyphosis remains a problem in posterior-only scoliosis surgery. As there has so far been no reliable method of predicting the intraoperative extent of kyphosis restoration or rib hump correction by posterior-only surgery, it has been difficult to determine the indication for an additional anterior release.

METHODS

The method described here circumvents this dilemma. Like an optional module, horacoscopically assisted release in prone position (TARP) can be added when it is obvious during posterior surgery that the correction is insufficient.

RESULTS

Between 1996 and 2005, a total of 161 patients (115 male, 46 female) under the age of 30, including 113 cases of idiopathic scoliosis, were released by simultaneous TARP and posterior surgery. Using the two-portal technique, 131 were mobilized from the right and 30 from the left hand side. Average surgical time spanned 69 min, in which on average 3.2 apical segments were addressed. In 3 individuals, an additional retroperitoneoscopic release was used to liberate a rigid lumbar curve. After 10 years, in a prospectively evaluated subgroup of 32 patients with adolescent idiopathic scoliosis, the index curve had maintained a coronal correction of 70 % (immediately post-surgery 75 %), kyphosis was permanently normalized at 30° (Th5-Th12), and indirect rib hump was reduced to 2.2 cm. In 23 out of 32 patients the lumbar curve corrected spontaneously, obviating the need for fusion. In 13 patients, the lower instrumented vertebra lay at Th12 or higher, thus leaving the thoraco-lumbar junction fairly free. Minor complications (Huang 1or 2) occurred in 4 patients; 1 patient with hematothorax required revision. A distance <25 mm from the spine to the chest wall precludes TARP. Other limitations (e.g., pleural adhesions) were not encountered.

CONCLUSION

Long-term evaluation after 10-18 years shows that an additional thoracoscopically assisted anterior release at the same time as a posterior standard scoliosis procedure is a justified and effective tool, yielding better results and maintaining them.

The Arabidopsis PLAT domain protein1 promotes abiotic stress tolerance and growth in tobacco

Plant growth and consequently crop yield can be severely compromised by abiotic and biotic stress conditions. Transgenic approaches that resulted in increased tolerance against abiotic stresses often were typically accompanied by adverse effects on plant growth and fitness under optimal growing conditions. Proteins that belong to the PLAT-plant-stress protein family harbour a single PLAT (Polycystin, Lipoxygenase, Alpha-toxin and Triacylglycerol lipase) domain and are ubiquitously present in monocot and dicot plant species. Until now, only limited data is available for PLAT-plant-stress family members, which suggested that these proteins in general could promote tolerance towards stress responses. We studied the function of the Arabidopsis PLAT-plant-stress protein AtPLAT1 employing heterologous gain-of-function analysis in tobacco. AtPLAT1 conferred increased abiotic stress tolerance in tobacco, evident by improved tolerance towards cold, drought and salt stresses, and promoted growth, reflected by a faster development under non-stressed conditions. However, the overexpression of AtPLAT1 in tobacco reduced the tolerance towards biotic stress conditions and, therefore, could be involved in regulating the crosstalk between abiotic and biotic stress responses. Thus, we showed that heterologously expressed AtPLAT1 functions as positive regulator of abiotic stress tolerance and plant growth, which could be an important new asset for strategies to develop plants with improved abiotic stress tolerance, without growth and subsequent yield penalties under optimal growth conditions.

[Causes and calculated predictors of a Duchenne gait in adolescents and young adults with cerebral palsy]

BACKGROUND

Adolescents with cerebral palsy often complain about a Duchenne gait, which increases the load on the spine, the energy consumption and therefore decreases gait efficiency. However the underlying causes of a Duchenne gait in patients with CP are not clearly researched yet. Nevertheless there is an assumption that excessive trunk lean might assist foot clearance to compensate for muscle weakness or contractures of the legs. In particular weakness, secondary to surgical soft tissue muscle tendon lengthening in childhood, might predispose patients to greater compensatory movements of the trunk. Therefore the aim of this study was to estimate the prevalence, underlying causes and calculated predictors for a Duchenne gait on CP patients with and without previous muscle tendon lengthening.

PATIENTS, MATERIALS AND METHODS

50 CP patients between 12 and 22 years with diplegia and GMFCS II (GMFCS: Gross Motor Function Classification System) participated in this study. 25 patients had no previous surgeries (CP-0). 25 patients had previous calf, hamstrings and/or adductor muscle tendon lengthening surgeries (CP-1). Data of 20 typically developed adolescents served as controls (TD). Gait was analysed using an instrumented gait analysis system (Vicon, Oxford, UK) The parameter "thorax obliquity range" (TOR) investigated the dimension of Duchenne gait.

RESULTS

CP-0 showed a prevalence of 72 %, CP-1 of 66 % for Duchenne gait. TOR was 5 ± 2°, 16 ± 8° and 16 ± 8°, for TD, CP-0 and CP-1, respectively. CP-0 and CP-1 showed significant differences in TOR between TD (both p < 0.001), but not between CP-0 and CP-1 (p = 1.0). Passive hip abduction range of motion (ROM) showed no significant correlation to TOR in both groups, whereas hip abduction muscle strength revealed significant correlation (rs = - 0.37) in CP-0. Best gait predictors in CP-0 patients were increased hip generation work (stance = st) and ankle dorsi flexion (swing = sw), together explaining 47 % of the variance in TOR. In CP-1 best gait predictors were increased hip generation work (st) as well as reduced knee flexion (sw) and ankle generation work (st), explaining 31 % of the variance in TOR.

CONCLUSION

With a prevalence of 66 % or higher Duchenne gait is a serious gait pathology in CP. Neither the hypothesis that previous muscle tendon lengthening nor that hip adductor contractures increase Duchenne gait could be confirmed in this study. Weak hip abductor muscle strength only showed a small correlation in CP-0. Best predictor in both groups was hip generation work (st). Certain hip abductors (M. gluteus medius ventral; M. gluteus minimus; M. tensor fasciae latae) function also as hip flexors and internal rotators. This leads to the hypothesis that during stance the Duchenne gait unloads the hip abductor muscles and therefore decreases the effect of internal rotation and hip flexion which leads to improved dynamic power of the hip for propulsion. In consequence the resultant hip extension moment increases by reducing the hip flexion moment. Presumably this is due to the fact that patients with CP show a reduced selective muscle control. For CP patients the negative effects of the common pelvis drop and internal rotation of the hip during gait decrease.

The Arabidopsis PLAT domain protein1 is critically involved in abiotic stress tolerance

Despite the completion of the Arabidopsis genome sequence, for only a relatively low percentage of the encoded proteins experimental evidence concerning their function is available. Plant proteins that harbour a single PLAT (Polycystin, Lipoxygenase, Alpha-toxin and Triacylglycerol lipase) domain and belong to the PLAT-plant-stress protein family are ubiquitously present in monocot and dicots. However, the function of PLAT-plant-stress proteins is still poorly understood. Therefore, we have assessed the function of the uncharacterised Arabidopsis PLAT-plant-stress family members through a combination of functional genetic and physiological approaches. PLAT1 overexpression conferred increased abiotic stress tolerance, including cold, drought and salt stress, while loss-of-function resulted in opposite effects on abiotic stress tolerance. Strikingly, PLAT1 promoted growth under non-stressed conditions. Abiotic stress treatments induced PLAT1 expression and caused expansion of its expression domain. The ABF/ABRE transcription factors, which are positive mediators of abscisic acid signalling, activate PLAT1 promoter activity in transactivation assays and directly bind to the ABRE elements located in this promoter in electrophoretic mobility shift assays. This suggests that PLAT1 represents a novel downstream target of the abscisic acid signalling pathway. Thus, we showed that PLAT1 critically functions as positive regulator of abiotic stress tolerance, but also is involved in regulating plant growth, and thereby assigned a function to this previously uncharacterised PLAT domain protein. The functional data obtained for PLAT1 support that PLAT-plant-stress proteins in general could be promising targets for improving abiotic stress tolerance without yield penalty.

A conserved peptide pattern from a widespread microbial virulence factor triggers pattern-induced immunity in Arabidopsis

Microbe- or host damage-derived patterns mediate activation of pattern-triggered immunity (PTI) in plants. Microbial virulence factor (effector)-triggered immunity (ETI) constitutes a second layer of plant protection against microbial attack. Various necrosis and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs) produced by bacterial, oomycete and fungal microbes are phytotoxic virulence factors that exert immunogenic activities through phytotoxin-induced host cell damage. We here show that multiple cytotoxic NLPs also carry a pattern of 20 amino acid residues (nlp20) that triggers immunity-associated plant defenses and immunity to microbial infection in Arabidopsis thaliana and related plant species with similar characteristics as the prototype pattern, bacterial flagellin. Characteristic differences in flagellin and nlp20 plant responses exist however, as nlp20s fail to trigger extracellular alkalinization in Arabidopsis cell suspensions and seedling growth inhibition. Immunogenic nlp20 peptide motifs are frequently found in bacterial, oomycete and fungal NLPs. Such an unusually broad taxonomic distribution within three phylogenetic kingdoms is unprecedented among microbe-derived triggers of immune responses in either metazoans or plants. Our findings suggest that cytotoxic NLPs carrying immunogenic nlp20 motifs trigger PTI in two ways as typical patterns and by inflicting host cell damage. We further propose that conserved structures within a microbial virulence factor might have driven the emergence of a plant pattern recognition system mediating PTI. As this is reminiscent of the evolution of immune receptors mediating ETI, our findings support the idea that there is a continuum between PTI and ETI.

Immune receptor complexes at the plant cell surface

Immunity to microbial infection is a common feature of metazoans and plants. Plants employ plasma membrane and cytoplasmic receptor systems for sensing microbe-derived or host-derived patterns and effectors and to trigger inducible immune defenses. Different biochemical types of plasma membrane immune receptors mediate recognition predominantly of peptide and carbohydrate patterns. Current research highlights the role of immune receptor complex formation in plant immunity. In particular, ligand binding by immune receptors generates molecular surfaces that enable either receptor homo-dimerization or co-receptor recruitment for subsequent signal transduction. New insight into negative regulatory principles of immune receptor function further suggests substantial dynamics in protein-protein interactions at the plasma membrane that we are only beginning to understand.

[Instrumented gait and movement analysis of musculoskeletal diseases]

Instrumented 3-dimensional gait analysis is increasingly being used for the evaluation of movement disorders in orthopedic and neurological musculoskeletal diseases. Due to the high reliability of the measurements the procedures are appropriate for diagnostic purposes as well as for outcome assessment after conservative or surgical interventions. Contrary to conventional clinical assessments gait analysis parameters are able to demonstrate a normal physiological gait pattern that can be achieved with improved kinematic and kinetic parameters. For a suitable application in clinically relevant problems the limitations of the procedures should be taken into account. Due to the high instrumental involvement combined with time and cost expenditure instrumented gait analysis will probably not develop to a clinical routine procedure. Nevertheless, an excellent set of information for answering clinical questions is provided. The present contribution presents selected measurement procedures and technologies and illustrates the wide variety of possibilities with the use of selected clinical examples.

Three-dimensional analysis of cranial growth from 6 to 12 months of age

The aim of this study was to generate three-dimensional data of the physiological growth of the infant's cranium in the significant growth phase from 6 to 12 months of age. In a longitudinal observational study non-invasive 3D data using an optical surface scanner were generated of the entire head of 52 Caucasian infants (27 females and 25 males) between the ages of 6 (T1) and 12 (T2) months. The circumference of the head increased by 6.51 per cent (from 43.50 to 46.33cm). Analysis of width and length showed that the head grows 2.84 per cent more in length, resulting in a decrease in the cranial index of 2.52 per cent (from 83.87 to 81.76 per cent). The highest increment observed was in the total volume of the cranium, with an increase of 18.76 per cent (from 1229.01 to 1459.57cm(3)). Comparison of the left and right sides of the head by measuring the diagonal symmetry difference showed a difference of only 0.37cm. Overall, the symmetry-related parameters showed an almost symmetric development of the cranium in infants. The findings should provide valuable information on physiological growth and development of the infant's cranium. Therefore the high growth rate of the cranium in the first year of life suggests that this period is a critical period in which the disruption of developmental processes may have long-lasting effects on the morphology of the cranium with a prognostically unfavourable effect of the further growth of the viscerocranium.

Experimental investigation and modeling of the kinetics of CCl4 pyrolysis behind reflected shock waves using high-repetition-rate time-of-flight mass spectrometry

The pyrolysis kinetics of CCl(4) behind reflected shock waves was studied with high-repetition-rate time-of-flight mass spectrometry. For modeling, quantum mechanical calculations were performed to evaluate the dissociation energies of CCl bonds for the different CCl(x) (x = 1 to 4) radicals. Good agreement with the JANAF thermochemical table was found. With the reaction mechanism developed for CCl(4) decomposition satisfactory agreement with experimental results was obtained. The investigations show the importance of C(2)Cl(2) formation for understanding the processes of carbon cluster growth leading to carbonaceous particle formation.

Avoiding CT scans in children with single-suture craniosynostosis

INTRODUCTION

During the last decades, computed tomography (CT) has become the predominant imaging technique in the diagnosis of craniosynostosis. In most craniofacial centers, at least one three-dimensional (3D) computed tomographic scan is obtained in every case of suspected craniosynostosis. However, with regard to the risk of radiation exposure particularly in young infants, CT scanning and even plain radiography should be indicated extremely carefully.

MATERIAL AND METHODS

Our current diagnostic protocol in the management of single-suture craniosynostosis is mainly based on careful clinical examination with regard to severity and degree of the abnormality and on ophthalmoscopic surveillance. Imaging techniques consist of ultrasound examination in young infants while routine plain radiographs are usually postponed to the date of surgery or the end of the first year. CT and magnetic resonance imaging (MRI) are confined to special diagnostic problems rarely encountered in isolated craniosynostosis. The results of this approach were evaluated retrospectively in 137 infants who were referred to our outpatient clinic for evaluation and/or treatment of suspected single suture craniosynostosis or positional deformity during a 2-year period (2008-2009).

RESULTS

In 133 (97.1%) of the 137 infants, the diagnosis of single-suture craniosynostosis (n = 110) or positional plagiocephaly (n = 27) was achieved through clinical analysis only. Two further cases were classified by ultrasound, while the remaining two cases needed additional digital radiographs. In no case was CT scanning retrospectively considered necessary for establishing the diagnosis. Yet in 17.6% of cases, a cranial CT scan had already been performed elsewhere (n = 16) or had been definitely scheduled (n = 8).

CONCLUSION

CT scanning is rarely necessary for evaluation of single-suture craniosynostosis. Taking into account that there is a quantifiable risk of developing cancer in further lifetime, every single CT scan should be carefully indicated.

X-ray studies of phase transitions of (Ca,Sr)-åkermanite solid solutions

The phase transitions of the solid solutions (Ca1- x Sr x )2MgSi2O7 (0 ≤ x ≤ 0.32) of modulated melilites are studied by X-ray diffraction. The variation of the intensity and the FWHM of satellite reflections reveal different transition temperatures. Two ranges of different ordering are found in the range of incommensurate modulation. The mechanism of the phase transition into the incommensurately modulated structure is discussed by including the diffuse scattering above the transition.

The commensurately modulated structure of the lock-in phase of synthetic Co-åkermanite, Ca2CoSi2O7

This paper deals with the structure determination of the lock-in phase of synthetic modulated Co-åkermanite, Ca2CoSi2O7. The structure determination of the (3 × 3 × 1) superstructure is based on X-ray data of a twinned single crystal taken at 130 K. The deformation modes in the commensurate lock-in phase are derived and compared with the deformations found by other authors in the incommensurate phase. A model for the driving force of the modulation in melilites in general is proposed: In order to release internal stress domains with clusters of 6-and 7-fold coordinated calcium are formed which are arranged in octagons.

[Recommendations for the management of ankylosing spodylitis after ASAS/EULAR. Evaluation in the German language area]

AIM

Our aim was to adapt and implement the evidence based recommendations for the management of ankylosing spodylitis (AS) of the "Assessments in AS" (ASAS) International Working Group together with the European League Against Rheumatism (EULAR) within the framework of a competence network (CN) in rheumatology in the German language area.

METHODS

The ASAS/EULAR project calculated the effective size (ES), rate ratio, number of patients requiring treatment (number needed to treat, NNT) and the incremental cost-effectiveness ratio (ICER). The strength of the recommendations was determined through the evidence level found in the literature, the risk-benefit trade-off and the clinical experience of the experts. The recommendations were recently published in English. All of the centers taking part in the study area Spondyloarthritis (SpA) CN, as well as an additional 35 experts, were sent the English manuscript. All 35 participants were asked to evaluate the ten main management recommendations on a scale from 0 to 10.

RESULTS

The recommendations encompass the use of drugs such as non-steroid anti-inflammatories (NSAR), which, along with conventional NSAR include coxibs and the parallel application of gastroprotectives, so called disease-modifying anti-rheumatic drugs, biologicals, simple analgesics, local and systematic glucocorticoids, non-drug therapies (such as patient training, medical training therapy and physiotherapy), in addition to surgical treatment methods. Moreover, three general recommendations were formulated and a therapy scheme created, taking into consideration the various clinical manifestations. The strength of the ASAS/EULAR recommendations was generally high. There was a marked consensus between the German speaking experts and the international proposal: a mean of 9.13 with relatively low variation between the recommendations.

SUMMARY

Ten key recommendations for the treatment of AS were developed. These were strengthened by a systematic search of the literature and by expert consensus. The large group of German speaking experts were largely in agreement with the proposal. This can be seen as a starting point for the dissemination and implementation of the recommendations.

Assessment of radiation exposure on a dual-source computed tomography-scanner performing coronary computed tomography-angiography

OBJECTIVE

The radiation exposure of a dual-source-64-channel multi-detector-computed-tomography-scanner (Somatom-Defintion, Siemens, Germany) was assessed in a phantom-study performing coronary-CT-angiography (CTCA) in comparison to patients' data randomly selected from routine scanning.

METHODS

240 CT-acquisitions of a computed tomography dose index (CTDI)-phantom (PTW, Freiburg, Germany) were performed using a synthetically generated Electrocardiography (ECG)-signal with variable heart rates (30-180 beats per minute (bpm)). 120 measurements were acquired using continuous tube-output; 120 measurements were performed using ECG-synchronized tube-modulation. The pulsing window was set at minimum duration at 65% of the cardiac cycle between 30 and 75 bpm. From 90-180 bpm the pulsing window was set at 30-70% of the cardiac cycle. Automated pitch adaptation was always used. A comparison between phantom CTDI and two patient groups' CTDI corresponding to the two pulsing groups was performed.

RESULTS

Without ECG-tube-modulation CDTI-values were affected by heart-rate-changes resulting in 85.7 mGray (mGy) at 30 and 45 bpm, 65.5 mGy/60 bpm, 54.7 mGy/75 bpm, 46.5 mGy/90 bpm, 34.2 mGy/120 bpm, 27.0 mGy/150 bpm and 22.1 mGy/180 bpm equal to effective doses between 14.5 mSievert (mSv) at 30/45 bpm and 3.6 mSv at 180 bpm. Using ECG-tube-modulation these CTDI-values resulted: 32.6 mGy/30 bpm, 36.6 mGy/45 bpm, 31.4 mGy/60 bpm, 26.8 mGy/75 bpm, 23.7 mGy/90 bpm, 19.4 mGy/120 bpm, 17.2 mGy/150 bpm and 15.6 mGy/180 bpm equal to effective doses between 5.5 mSv at 30 bpm and 2.6 mSv at 180 bpm. Significant CTDI-differences were found between patients with lower/moderate and higher heart rates in comparison to the phantom CTDI-results.

CONCLUSIONS

Dual source CTCA is particularly dose efficient at high heart rates when automated pitch adaptation, especially in combination with ECG-based tube-modulation is used. However in clinical routine scanning for patients with higher heart rates and corresponding enlarged pulsing window a significant different dose resulted.

[Reality of treatment of osteoporotic fractures in German trauma departments. A contribution for outcome research]

The implementation of clinical pathways has a proven positive effect on the diagnostic workup and initiation of therapy in osteoporotic fracture patients. Unlike in most countries, fracture care in Germany is provided by so-called trauma surgeons. Therefore, it is essential to focus on the trauma surgeon for correct diagnostic workup and therapy initiation after a fragility fracture. A questionnaire was mailed to 409 departments of traumatology inquiring about the existence of a standardized clinical pathway for diagnosis and treatment of patients with fragility fractures. One of the central issues of the survey was whether those pathways comply with national guidelines. Only institutions that stated that they followed a clinical pathway were analyzed. 80% of institutions took part in our survey, 35% of which reported following a defined clinical pathway. Diagnostic workup is in concordance with the national guidelines in 30%, and therapy is guideline-based in 51%, with 12% basing both diagnostic workup and therapy on the guidelines. Thus, the vast majority of German traumatology departments do not follow national guidelines regarding osteoporosis diagnostics and therapy in patients with fragility fractures, leading to a great opportunity to improve fragility fracture care by means of both education and interdisciplinary cooperation.

[Does timing of thoracic spine stabilization influence perioperative lung function after trauma?]

BACKGROUND

Proper timing of stabilization for spine injuries is discussed controversially. Whereas early repair of long bone fractures is known to reduce complications.

PATIENTS AND METHODS

We investigated retrospectively 48 patients who were stabilized in a ventrodorsal approach for fractures of the thoracic spine. Patients were divided into three groups. All patients in groups I and II presented radiological or clinical signs of lung contusion. Patients were stabilized in the prone position via single-step dorsal stabilization with internal transpedicular fixation and ventral fusion with titanium cage or autologous bone graft using a minimally invasive video-assisted thoracotomy.

RESULTS

The average duration of the procedures in group I was 213+/-40 min, in group II 250+/-75 min, and in group III 255+/-65 min (p: n.s.). Intraoperative blood loss did not differ significantly between the three groups. The PaO(2)/FiO(2) ratio improved in groups I and III, whereas in group II an significant impairment of lung function occurred perioperatively. Postoperative ICU stay was comparable in groups I and II (I: 10+/-5 days; II: 9+/-7 days); overall ICU stay tended to be shorter in group I versus II. The postoperative dependence on ventilator support did not differ significantly among the three groups. The mortality rate was 0% in this series.

CONCLUSION

Our data provide further evidence that early stabilization of combined thoracic and thoracic spine injuries is safe, does not alter perioperative lung function, and results in a reduced overall ICU stay.