Radiotherapy for patient with cardiac implantable electronic device, consensus from French radiation oncology society

Radiotherapy in patients with cardiac implantable electronic device such as pacemakers or defibrillators, is a clinical situation that is becoming increasingly common. There is a risk of interaction between the magnetic field induced by accelerators and the cardiac implantable electronic device, but also a risk of device dysfunction due to direct and/or indirect irradiation if the cardiac implantable electronic device is in the field of treatment. The risk can be dose-dependent, but it is most often independent of the total dose and occurs randomly in case of neutron production (stochastic effect). The presence of this type of device is therefore described as a contraindication for radiotherapy by the French national agency for the safety of medicines and health products (Agence nationale de sécurité du médicament et des produits de santé, ANSM). Nevertheless, since radiotherapy is often possible, it is advisable to respect the recommendations of good practice, in particular the eligibility criteria, the monitoring modalities before, during and after irradiation according to the type of treatment, the dose and the characteristics of the cardiac implantable electronic device. It is sometimes necessary to discuss repositioning the device and/or modifying the treatment plan to minimize the risk of cardiac implantable electronic device dysfunction. We present the update of the recommendations of the French society of oncological radiotherapy on in patients with cardiac implantable electronic device.

Anatomical predictors of high grade atrioventricular conduction disorders in patients with specific pacemaker implanted after TAVI

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

STIM TAVI-MS study

Background

 The evolution of atrioventricular conduction disorders after transcatheter aortic valve implantation (TAVI) remains poorly understood. Recent studies have identified short membranous septum (MS) length, deep implantation depth (ID) or their relation as anatomic risk of high-grade AV block and permanent pacemaker implantation.

Purpose : We sought to examine whether the atrioventricular (AV) membranous septum (MS) measured by computed tomography (CT) and the depth of valve implantation measured from the final aortic angiogram could predict high-grade atrioventricular block (HG AVB) after TAVI, based on specific pacemaker memory data.

Methods

STIM-TAVI-MS was a prospective, multicentre observational study that enrolled patients implanted with a specific dual chamber pacemaker after TAVI, with the SafeR algorithm activated, allowing continuous monitoring of atrioventricular conduction. The primary endpoint was the occurrence of late (after Day 7) high-grade atrioventricular block(s) during the year after TAVI. We measured on CT scans the coronal MS lenght, infra-annular MS lenght and the quantification of calcifications, on the final angiogram after TAVI we measured the implant depth (ID) to identifie ΔID-MS corresponding to the difference between implant depth and MS length. The variables were compared with the occurrence of late HG-AVB on PM memory data.

Results : Among 82 patients, (mean age 84,5 years ± 4,8, self-expending valve n = 24, 29,3%), n = 47 (57.3%) had ≥1 late high-grade atrioventricular block. Mean coronal MS length was 8,1 ± 2,5 mm, mean infra annular MS was 3,4 ± 3.1 mm, mean calcification volume was 93.0 ± 88, 85,5± 104 and 141,5 ± 137,5 mm3 for the noncoronary, right coronary and left coronary cusp respectively. Mean implant depth was 7,3 ± 3,3mm, and mean ΔID-MS = -0,7 ± 4,1mm. There were no association between MS length (OR = 1,06; CI 0,91 to 1,24), ID (OR = 1,6; CI 0,85 to 2,9), nor ΔID-MS (OR = 0,67; CI 0,37 to 1,23) and late HG AVB. Calcification volume were not associated with late HG AVB.

Conclusion

In an high risk high grade AV block population after TAVI, anatomical analysis of MS length, degree of calcification, implant depth and ΔID-MS did not predict occurrence of late (> day 7 after TAVI ) high grade AV Blocks. Abstract Figure. CT scan A : aortic plane, B : MS lenght

P953Smartphone monitor kardia: an effective diagnostic tool for paroxysmal palpitations

Funding Acknowledgements

no grants to declare

OnBehalf

not applicable

Background : Paroxysmal palpitations are diagnostic challenge because the ECG and the 24-hour holter ECG monitoring without palpitations is usually normal. We report a 1 year experience of a new diagnostic tool for paroxysmal palpitations: the smartphone monitor Kardia®. Patients with paroxysmal palpitation and negative 24 hour holter ECG was ask to sent iECG during symptoms during the 1 month follow-up.

Results

Between January and December 2018, 20 patients have received Kardia®, mean age 40 years, the mean duration kardia-monitoring was 26 days. A total of 235 iECGs were sent by email, a median of 6 iECG/patients. 9 (45%) patients remained without rhythmic diagnosis (sinus rhythm, normal heart rate), 11 (55%) patients had at least one pathological iECG: 4 atrial fibrillation, 4 junctional tachycardia including 1 with paroxysmal pre-excitation, 2 atrial flutters. These diagnosis had therapeutic consequences: 2 AF ablations, 2 AF treated by antiarythmic drugs (AAD), 2 atrial flutters ablation, 1 ILR was implanted for absence of diagnosis with kardia®. The other patients without diagnosis at the time of palpitations were reassured on the absence of cardiac rhythm disturbance.

Conclusion

The purchase of 5 Kardia® as a new diagnostic tool for paroxtysmal palpitations is a reasonable investment for a cardiology derpartment, the diagnostic performance is higher than current standards (24 hours holters ECG monitoring), since it allows an arhythmic diagnosis in more than 50% of cases in 1 mounth. The main limitation is the selection of patients, most often young, who already have a smartphone and can send an email.

patient age (years) duration (days) i-ECG sent number diagnosis treatment patient 1 23 11 3 AF AF ablation patient 3 51 23 7 AF AA Drugs patient 10 65 20 5 AF AA Drugs patient 11 35 29 6 SVT : AVNRT no ablation patient 12 48 22 27 atrial flutter flutter ablation patient 13 34 1 13 SVT : AVNRT no ablation patient 14 56 7 18 atrial flutter flutter ablation patient 15 59 21 80 AF and PVC AF Ablation patient 16 50 1 3 SVT : AVRT no ablation patient 17 28 28 2 SVT : AVNRT no ablation patient 19 49 35 8 PVC AA Drugs 1 year kardia experience : diagnosis performance in the 11/20 patients with abnormal iECG

Abstract Figure. iECG : termination of SVT (patient 17)

Room temperature and low-field resonant enhancement of spin Seebeck effect in partially compensated magnets

Resonant enhancement of spin Seebeck effect (SSE) due to phonons was recently discovered in Y[Formula: see text]Fe[Formula: see text]O[Formula: see text] (YIG). This effect is explained by hybridization between the magnon and phonon dispersions. However, this effect was observed at low temperatures and high magnetic fields, limiting the scope for applications. Here we report observation of phonon-resonant enhancement of SSE at room temperature and low magnetic field. We observe in Lu[Formula: see text]BiFe[Formula: see text]GaO[Formula: see text] an enhancement 700% greater than that in a YIG film and at very low magnetic fields around 10[Formula: see text] T, almost one order of magnitude lower than that of YIG. The result can be explained by the change in the magnon dispersion induced by magnetic compensation due to the presence of non-magnetic ion substitutions. Our study provides a way to tune the magnon response in a crystal by chemical doping, with potential applications for spintronic devices.

A bioactive injectable bulking material; a potential therapeutic approach for stress urinary incontinence

Stress urinary incontinence (SUI) is a life changing condition, affecting 20 million women worldwide. In this study, we developed a bioactive, injectable bulking agent that consists of Permacol™ (Medtronic, Switzerland) and recombinant insulin like growth factor-1 conjugated fibrin micro-beads (fib_rIGF-1) for its bulk stability and capacity to induce muscle regeneration. Therefore, Permacol™ formulations were injected in the submucosal space of rabbit bladders. The ability of a bulking material to form a stable and muscle-inducing bulk represents for us a promising therapeutic approach to achieve a long-lasting treatment for SUI. The fib_rIGF-1 showed no adverse effect on human smooth muscle cell metabolic activity and viability in vitro based on AlamarBlue assays and Live/Dead staining. Three months after injection of fib_rIGF-1 together with Permacol™ into the rabbit bladder wall, we observed a smooth muscle tissue like formation within the injected materials. Positive staining for alpha smooth muscle actin, calponin, and caldesmon demonstrated a contractile phenotype of the newly formed smooth muscle tissue. Moreover, the fib_rIGF-1 treated group also improved the neovascularization at the injection site, confirmed by CD31 positive staining compared to bulks made of Permacol^TM only. The results of this study encourage us to further develop this injectable, bioactive bulking material towards a future therapeutic approach for a minimal invasive and long-lasting treatment of SUI.

Fiber density of collagen grafts impacts rabbit urethral regeneration

There is a need for efficient and “off-the-shelf” grafts in urethral reconstructive surgery. Currently available surgical techniques require harvesting of grafts from autologous sites, with increased risk of surgical complications and added patient discomfort. Therefore, a cost-effective and cell-free graft with adequate regenerative potential has a great chance to be translated into clinical practice. Tubular cell-free collagen grafts were prepared by varying the collagen density and fiber distribution, thereby creating a polarized low fiber density collagen graft (LD-graft). A uniform, high fiber density collagen graft (HD-graft) was engineered as a control. These two grafts were implanted to bridge a 2 cm long iatrogenic urethral defect in a rabbit model. Histology revealed that rabbits implanted with the LD-graft had a better smooth muscle regeneration compared to the HD-graft. The overall functional outcome assessed by contrast voiding cystourethrography showed patency of the urethra in 90% for the LD-graft and in 66.6% for the HD-graft. Functional regeneration of the rabbit implanted with the LD-graft could further be demonstrated by successful mating, resulting in healthy offspring. In conclusion, cell-free low-density polarized collagen grafts show better urethral regeneration than high-density collagen grafts.

Microfluidic production of bioactive fibrin micro-beads embedded in crosslinked collagen used as an injectable bulking agent for urinary incontinence treatment

Endoscopic injection of bulking agents has been widely used to treat urinary incontinence, often due to urethral sphincter complex insufficiency. The aim of the study was to develop a novel injectable bioactive collagen-fibrin bulking agent restoring long-term continence by functional muscle tissue regeneration. Fibrin micro-beads were engineered using a droplet microfluidic system. They had an average diameter of 140 μm and recombinant fibrin-binding insulin-like growth factor-1 (α₂PI_1-8-MMP-IGF-1) was covalently conjugated to the beads. A plasmin fibrin degradation assay showed that 72.5% of the initial amount of α₂PI_1-8-MMP-IGF-1 loaded into the micro-beads was retained within the fibrin micro-beads. In vitro, the growth factor modified fibrin micro-beads enhanced cell attachment and the migration of human urinary tract smooth muscle cells, however, no change of the cellular metabolic activity was seen. These bioactive micro-beads were mixed with genipin-crosslinked homogenized collagen, acting as a carrier. The collagen concentration, the degree of crosslinking, and the mechanical behavior of this bioactive collagen-fibrin injectable were comparable to reference samples. This novel injectable showed no burst release of the growth factor, had a positive effect on cell behavior and may therefore induce smooth muscle regeneration in vivo, necessary for the functional treatment of stress and other urinary incontinences.

STATEMENT OF SIGNIFICANCE

Urinary incontinence is involuntary urine leakage, resulting from a deficient function of the sphincter muscle complex. Yet there is no functional cure for this devastating condition using current treatment options. Applied physical and surgical therapies have limited success. In this study, a novel bioactive injectable bulking agent, triggering new muscle regeneration at the injection site, has been evaluated. This injectable consists of cross-linked collagen and fibrin micro-beads, functionalized with bound insulin-like growth factor-1 (α₂PI_1-8-MMP-IGF-1). These bioactive fibrin micro-beads induced human smooth muscle cell migration in vitro. Thus, this injectable bulking agent is apt to be a good candidate for regeneration of urethral sphincter muscle, ensuring a long-lasting treatment for urinary incontinence.

[How do Swiss family physicians treat subclinical hypothyroidism?]

Subclinical hypothyroidism is a common condition, and its prevalence increases with age. Currently, guidelines regarding the screening and treatment of subclinical hypothyroidism are controversial. An international survey of general practitioners (GPs), to which Swiss GPs also contributed, showed large inter-country variations in treatment strategies for subclinical hypothyroidism. These differences are mainly explained by the lack of strong evidence for the management of this condition. The European randomized-controlled clinical trial TRUST should help clarify recommendations for screening and thyroxin replacement for the elderly with subclinical hypothyroidism. Working in close collaboration with GPs in Switzerland for the recruitment of patients will ensure that the findings from this study will be applicable to primary care settings.

Effects of acute and long-term treatment with neuroleptics on regional telencephalic neurotensin levels in the male rat

By means of radioimmunoassay measurements of regional neurotensin (NT) levels in the forebrain of the male rat it was shown that selective D2 DA receptor antagonists, such as haloperidol and sulpiride, and unselective D1 and D2 antagonists such as thioridazine, flupenthixol clozapine and fluperlapine, can acutely increase NT levels in the striatum and the nucleus accumbens without affecting NT levels in the amygdaloid or anteromedial frontal cortex. Conversely, acute treatment with the D1 DA receptor antagonist Schering 23390 (SCH 23390) produced a selective reduction of striatal NT levels. After long-term treatment clozapine, fluperlapine or SCH 23390, tolerance developed with regard to their ability to modulate striatal and accumbens levels. No tolerance occurred after chronic haloperidol, chlorpromazine and sulpiride. The results indicate that the acute administration of D1 and D2 DA receptor antagonists differentially modifies NT levels in the striatum and nuc. accumbens, and that antipsychotic drugs showing a relative lack of extrapyramidal side effects may be characterised by a failure to maintain increased NT levels in the basal ganglia upon long-term treatment.

The genetic structure of the plant pathogenic fungus Melampsora larici-populina on its wild host is extensively impacted by host domestication

Wild and cultivated plants represent very different habitats for pathogens, especially when cultivated plants bear qualitative resistance genes. Here, we investigated to what extent the population genetic structure of a plant pathogenic fungus collected on its wild host can be impacted by the deployment of resistant cultivars. We studied one of the main poplar diseases, poplar rust, caused by the fungus Melampsora larici-populina. A thousand and fifty individuals sampled from several locations in France were phenotyped for their virulence profile (ability to infect or not the most deployed resistant cultivar 'Beaupré'), and a subset of these was genotyped using 25 microsatellite markers. Bayesian assignment tests on genetic data clustered the 476 genotyped individuals into three genetic groups. Group 1 gathered most virulent individuals and displayed evidence for selection and drastic demographic changes resulting from breakdown of the poplar cultivar 'Beaupré'. Group 2 comprised individuals corresponding to ancestral populations of M. larici-populina naturally occurring in the native range. Group 3 displayed the hallmarks of strict asexual reproduction, which has never previously been demonstrated in this species. We discuss how poplar cultivation has influenced the spatial and genetic structure of this plant pathogenic fungus, and has led to the spread of virulence alleles (gene swamping) in M. larici-populina populations evolving on the wild host.

Bioresorbable Microspheres as Injectable Cell Carrier: FRom Preparation to in Vitro Evaluation

A new approach to the vesico-ureteral reflux could be a local regeneration of the defective vesicoureteral junction by transplanting living cells to the target site. The aim of this work is to provide a long-term effective treatment by producing bioresorbable microspheres which can act as support matrix for those cells, with the goal of an in vivo transfer of the in vitro cultured cells with a minimal surgical procedure. After microsphere degradation, the cells should be integrated into the muscular structure of the junction. Most innovative is that these are cultured muscle and urothelial cells from the bladder of the same patient.

Grafted Poly(acrylic acid) Brushes for Cell-Surface Interactions

Poly(acrylic acid) (PAA) was grafted onto RF plasma treated PET films and onto SiO2 covered glass surfaces. PET films with various amounts of grafted PAA (0.4, 5, 11 and 19 μm/cm2) were immersed into a solution of collagen to allow for polyionic complex formation as a method for protein immobilization. It was found that the amount of complexed collagen was close to proportional to the amount of PAA. A closer investigation of the optical density of the PAA brushes close to the glass surface wa was performed using Reflectometric Inteference Spectroscopy. The supression of possibilities of extension and collaps of the brushes upon variation in pH is suggested to be caused by polyionic crosslinking between protonated collagen and deprotonated PAA. Such PAA-collagen surfaces with PAA concentrations lower that 10 μm/cm2 were shown to be suitable substrates for growth of human bladder smooth muscle cells.

Bacteriocin Typing of Burkholderia (Pseudomonas) solanacearum Race 1 of the French West Indies and Correlation with Genomic Variation of the Pathogen

Burkholderia solanacearum race 1 isolates indigenous to the French West Indies were characterized by bacteriocin typing and two genomic fingerprinting methods: pulsed-field gel electrophoresis of genomic DNA digested by rare-cutting restriction endonucleases (RC-PFGE) and PCR with primers corresponding to repetitive extragenic palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC), and BOX elements (collectively known as rep-PCR). The survey comprised 24 reference strains and 65 isolates obtained from a field trial in Guadeloupe in 1993. Comparison of the data identified RC-PFGE as the most discriminatory method, delineating 17 pulsed-field gel profile types. rep-PCR and bacteriocin typing identified nine rep-PCR profile types and nine bacteriocin groups. Independent determination of similarity coefficients and clustering of RC-PFGE and rep-PCR data identified six groups common to both sets of data that correlated to biovar and bacteriocin groups. Further study of bacteriocin production in planta gave results consistent with in vitro bacteriocin typing. It was observed that spontaneous bacteriocin-resistant mutants exhibited a cross-resistance to other bacteriocins as identified by the typing scheme and that such mutants possessed a selective advantage for growth over isogenic nonmutants in the presence of a bacteriocin. The results are significant in the search for biological control of disease by nonpathogenic mutants of the wild-type organism.

Metabolic and Genotypic Fingerprinting of Fluorescent Pseudomonads Associated with the Douglas Fir-Laccaria bicolor Mycorrhizosphere

A collection of 300 isolates of fluorescent pseudomonads was established from Douglas fir-Laccaria bicolor mycorrhizas and mycorrhizosphere and from adjacent bulk soil. These isolates were first phenotypically characterized with the Biolog method. Taxonomic identification assigned 90% of the isolates to the different biovars of Pseudomonas fluorescens, with inverted frequencies of biovars V and I from the bulk soil to the mycorrhizas, suggesting that the mycorrhizas exert a selective stimulation of the P. fluorescens bv. I and a counterselection of the P. fluorescens bv. V present in the soil. Multivariate analyses of the carbon source utilization data led to the definition of homogenous metabolic groups and to the identification of the most discriminating substrates for each group. The isolates from the mycorrhizosphere and from the mycorrhizas seem to preferentially utilize carbohydrates, in particular trehalose, which is the most abundant carbohydrate accumulated in the mycelium of L. bicolor. The results suggest that L. bicolor exerts a trehalose-mediated selection on the fluorescent pseudomonads present in the vicinity of the mycorrhizas. Isolates of P. fluorescens from the mycorrhizosphere and mycorrhizas were then genotypically characterized by restriction fragment length polymorphism of PCR-amplified 16S rRNA genes and enterobacterial repetitive intergenic consensus-PCR DNA fingerprinting. Both methods revealed a high genetic polymorphism within the population studied, which was well correlated with the phenotypic characterization.

[Overweight and obesity in children: known facts and new trends]

The prevalence of overweight and obesity in children is increasing. A growing number of children are thus suffering from complications of obesity. Contributing factors can be found on an individual level as well as in the familial and social environment of affected children. Currently there is no single evidence-based treatment strategy available. Studies from family practice are scarce. Multimodal, long-term, easily accessible treatments as offered in family practice are promising and likely to be cost-effective. The sustainability of these changes in behavior still needs to be demonstrated.

[Pediatrics]

This article summarizes the medical progress achieved in 2 frequent and 2 rare pathologies: 1. Cryptorchidism should be operated around 12 months of age and hormonal treatment abandoned in order to maintain fertility and avoid development of testicular tumors. 2. For the treatment of streptococcal pharyngitis oral cephalosporins for 4 to 5 days are equivalent to a Penicillin treatment of 10 days. 3. Thanks to carvedilol (a beta-blocker agent), levosimendan (a calcium sensibiliser) and nesiritide (an analog to the natriuretic peptide) a new hormonal approach to cardiac failure is possible. 4. Corticosteroids allow to improve quality of live and life expectancy in Duchenne muscular dystrophy, provided treatment starts early and a multidisciplinary approach is assured.

First Report of Phytophthora ramorum on Ornamental Plants in France

In April 2002, Phytophthora ramorum was associated with twig blight and brown spots on Rhododendron spp. leaves from a nursery in France. The isolate was identified by its morphological characters on V8 agar: slow growth, deciduous and semipapillate sporangia, and abundant production of large chlamydospores (3). The identification was confirmed by ITS rDNA sequencing. During 2002, P. ramorum was also isolated from diseased Viburnum tinus and V. × bodnantense plants exhibiting symptoms of wilting and stem base discoloration. Subsequently, repeated surveys for P. ramorum were carried out in nurseries and areas surrounding nurseries throughout France. Since 2004, a large range of known hosts were investigated in approximately 2,000 nurseries and 200 other sites each year. P. ramorum was detected exclusively in nurseries at 29 locations in 2002, 9 in 2003, 23 in 2004, 17 in 2005, and 19 in 2006. Rhododendron spp. and occasionally V. tinus were the major hosts. In addition, the pathogen was detected for the first time on Pieris japonica in two nurseries in 2005 and on Camellia sp. in one nursery in 2006 from plants exhibiting leaf and twig blight. In both cases, P. ramorum had already been detected on Rhododendron spp. in the same nurseries. Most of the infected plants were found in northwestern France (Bretagne and Pays-de-la-Loire), or came from this region, which is the main rhododendron-growing area in France. In some cases, plants were imported from Belgium or the Netherlands. P. ramorum was also detected in a nursery in soil close to diseased Rhododendron spp. plants and pond water used for irrigation by using a combination of baiting with Rhododendron spp. leaves and PCR assay with species-specific primers (1). Overall, approximately 1% of the investigated nurseries were found positive each year, and this ratio was quite stable from 2004 to 2006. To date, P. ramorum has not been detected outside of nurseries, although many surveys were conducted on the west coast of France where the risk is considered to be high because of a favorable mild and humid climate and the presence of suitable hosts. In addition, 78 isolates of P. ramorum collected between 2002 and 2004 on Rhododendron spp. and V. tinus were found to be of A1 mating type based on pairings with P. cryptogea A1 and A2 mating types (2). References: (1) K. J. Hayden et al. Phytopathology 94:1075, 2004. (2) S. Werres and B. Zielke J. Plant Dis. Prot. 110:129, 2003. (3) S. Werres et al. Mycol. Res. 105:1155, 2001.

[Antenatally detected hydronephrosis: practical approach for the pediatrician]

Approximately 1% of the fetuses present some dilatation of their urinary tract in utero. More than 50% of these antenatally detected hydronephrosis will disappear spontaneously after birth. The other 50% comprises ureteropelvic junction obstruction, vesico-ureteral reflux and primary megaureters. Postnatal radiological evaluation (renal ultrasonography and VCUG) is performed in every infant with a significantly dilated renal pelvis (> 8 mm between 20 and 30 weeks or > 10 mm after 30 weeks in utero). Renal nuclear scan should be done in every child with significant/worsening post-natal hydronephrosis. Antibioprophylaxis will be started from birth to prevent urinary tract infection. Medical or surgical approach will be chosen in the light of the uroradiological exam results and the clinical progress.

From arteriographies to computational flow in saccular aneurisms: the INRIA experience

Saccular aneurisms illustrate usefulness and possible techniques of image-based modeling of flow in diseased vessels. Aneurism flow is investigated in order to estimate the rupture risk, assuming that the pressure is the major factor and that high-pressure zones are correlated to within-wall strong-stress concentrations. Computational flow is also aimed at providing additional arguments for the treatment strategy. Angiographies of aneurismal vessels of large and medium size are processed to provide three-dimensional reconstruction of the vessel region of interest. Different reconstruction techniques are used for a side and a terminal aneurisms. Reconstruction techniques may lead to different geometries especially with poor input data. The associated facetisation is improved to get a computation-adapted surface triangulation, after a treatment of vessel ends and mesh adaptation. Once the volumic mesh is obtained, the pulsatile flow of an incompressible Newtonian blood is computed using in vivo non-invasive flowmetry and the finite element method. High pressure zones are observed in the aneurism cavity. The pressure magnitude in the aneurism, the location and the size of high pressure zones depend mainly on the aneurism implantation on the vessel wall and its orientation with respect to the blood flux in the upstream vessel. The stronger the blood impacts on the aneurismal wall the higher the pressure. The state of the aneurism neck, where a high-pressure zone can occur, and the location of the aneurism, with an easy access or not, give arguments for the choice between coiling and surgical clipping. Mesh size and 3D reconstruction procedure affect the numerical results. Helpful qualitative data are provided rather than accurate quantitative results in the context of multimodeling.

[Arthralgia, eosinophilia, proteinuria and diuretics-resistant leg edemas]

We report the case of a patient with eosinophilic fasciitis, a rare disease related to systemic sclerodermia and other fibrosing disorders. An involvement of the kidneys--like in this patient with proteinuria and hypoproteinemia--has been described in the literature but is very rare. We discuss diagnostic procedures and novel therapeutic options as combination therapies with steroids, methotrexate and ciclosporine A.

Assessment of the biological performance of the needle-free injector INJEX using the isolated porcine forelimb

BACKGROUND

The development and utilization of novel needle-free injection devices in order to minimize needle stick injuries make increasing demands for suitable assay systems, which reflect the physiological situation in humans as close as possible.

OBJECTIVES

It was therefore the goal of the present study to test the biological performance of a needle-free injector (INJEX) by the use of porcine skin as a model with a high predictive value for the feasibility in humans because of its close similarity to human skin.

METHODS

In order to use porcine skin in the context of the underlying tissues, the isolated porcine forelimb was chosen as an assay model for use with the INJEX injector. Ink or the fluorescent dye fluorescein-isothiocyanate was injected and the penetration depth was determined metrically and dye distribution histologically. To assess the resorption of heparin, needle injection was compared with needle-free injection in a perfused limb model.

RESULTS

Increasing amounts of ink increasingly penetrated into subcutaneous tissue layers in a cone-shaped manner mainly following lead structures. Penetration was hampered by skin thickness and by the deep muscle fascia, which served as a penetration barrier. Resorption of heparin was similar irrespective of injection by the use of a needle or the INJEX device.

CONCLUSIONS

The isolated porcine forelimb serves as a versatile tool for the assessment of the biological performance of needle-free injection devices such as INJEX. Further studies are necessary to correlate the model for drug delivery in humans.

First Report of Melampsora larici-populina on Populus spp. in Eastern North America

In September 2002, yellow spots were observed on the leaf surface of a hybrid poplar (Populus maximowiczii Henry × P. balsamifera L.) grown at the Berthier forest nursery (46°2'N, 73°11'W) in the St. Lawrence Valley (Lanaudière Region, Québec, Canada). Disease severity was low, but the pathogen was present on a hybrid that was previously thought to be resistant to Melampsora medusae Thuem, the only reported poplar rust in eastern North America. Uredinia typical of a Melampsora sp. were observed on the abaxial leaf surface. The observed urediniospores were longer (32 to 48 μm) than the expected range for M. medusae (23 to 35 μm) and possessed an apical bald spot; thick paraphyses were also observed. These characteristics are diagnostic of M. larici-populina Kleb (2). Samples were deposited in the National Mycological Herbarium of Canada (DAOM 232107 and 232108) and in the Quebec Forest Biology Herbarium (QFB14703 and 14704). DNA was extracted from uredinia, and the internal transcribed spacer (ITS) of the ribosomal RNA gene was amplified and sequenced (GenBank Accession Nos. AY429656 and AY429657). There was a 100% match between the two sequences obtained and that of M. larici-populina (GenBank Accession No. AY375267), but there was approximately 12% divergence with the ITS sequence of M. medusae (GenBank Accession No. AY375273-5). This is the first report of M. larici-populina in eastern North America. This fungus was reported on P. trichocarpa × P. deltoides hybrids in the western United States in the early 1990s (1). It appears that M. larici-populina can overwinter in Québec because it was observed again at the nursery in September 2003. The occurrence of M. larici-populina in eastern North America has direct implications for the poplar industry since the host specificities of M. medusae and M. larici-populina differ; P. balsamifera and P. maximowiczii are sensitive to M. larici-populina (3). Hybrids with P. balsamifera or P. trichocarpa components may be particularly at risk. References: (1) G. Newcombe and G. A. Chastagner. Plant Dis. 77:532, 1993. (2) J. Pinon. Eur. J. For. Pathol. 3:221, 1973. (3) J. Pinon. Silvae Genet. 41:25, 1992.

Unilateral ureteropelvic junction obstruction in children: long-term followup after unilateral pyeloplasty

PURPOSE

The benefit of surgery on renal function in unilateral ureteropelvic junction stenosis (UPJS) is still debated. We evaluated renal function outcome after unilateral pyeloplasty in 53 children.

MATERIALS AND METHODS

We retrospectively reviewed 123I-hippuran renography performed at diagnosis and 5 to 15 years (mean +/- SD 7 +/- 3 years) after successful pyeloplasty. UPJS was prenatally detected in 26 children because of urinary tract infection in 17 and miscellaneous reasons in 10. Relative function (RF) and absolute function were measured on background corrected renograms. Absolute function of the affected and contralateral kidneys was determined by an accumulation index (AI), representing the percent injected dose extracted by each kidney 30 to 90 seconds after the heart peak.

RESULTS

Preoperatively 33 of the 53 UPJS kidneys had a decreased AI but only 8 had a RF of less than 40%, which was improved in 7 at followup. In addition, the AI improved in 29 kidneys, of which 19 (36%) normalized. Of the UPJS kidneys 14 had an initially decreased AI that remained abnormal at followup. In these kidneys preoperative RF was less than 40% in all. At followup RF was greater than 40% in 4 children, in whom the AI of the UPJS kidney did not improve but the AI of the contralateral one decreased from supranormal to normal. Seven contralateral kidneys had a supranormal AI, whereas the AI remained normal in 3, of which the RF in the UPJS kidney remained at less than 40%. The AI and RF were normal in 20 UPJS kidneys and remained normal.

CONCLUSIONS

When normal, the AI and RF reflected renal function outcome similarly. The AI added relevant information in UPJS kidneys with impaired function, showing compensation of the contralateral kidney.

Repeated surgical excision for an unusual variant of nephroblastoma: case report and review of the literature

Bilateral fetal rhabdomyomatous nephroblastoma is a rare variant of Wilms' Tumor. The authors report the evolution over 48 months of a 10-month-old baby with bilateral nephroblastoma for which a left nephrectomy was initially performed. A right kidney tumor was enucleated preserving the kidney. The transformation of the primary tumor into a completely differentiated cystic nephroblastoma or nephromalike tumor and the appearance of a metachronous lesion was seen. This report emphasizes the role of nephron-sparing surgery in bilateral Wilms' Tumor when a benign transformation occurs under chemotherapy.

Partial Resistance to Melampsora larici-populina Leaf Rust in Hybrid Poplars: Genetic Variability in Inoculated Excised Leaf Disk Bioassay and Relationship with Complete Resistance

ABSTRACT Inoculated excised leaf disk technique allows decomposition of poplar partial resistance to Melampsora larici-populina leaf rust into key epidemiological components such as latent period (LP), uredinia number (UN), uredinia size (US), and spore production (SP) for a given M. larici-populina strain under controlled environmental conditions. Three hundred thirty-six genotypes from an interspecific Populus deltoides x P. trichocarpa F(1) progeny segregating for complete resistance to M. larici-populina strain 93ID6 were inoculated with M. larici-populina strain 93CV1. This strain was able to infect the whole family, except few probable recombinants. LP, final UN, and final US after one infectious cycle proved to be relevant complementary descriptors of partial resistance. Area under the disease progress curve and other parameters of uredinia appearance dynamics did not yield additional information. Indirect assessment of SP by US scoring was reliable and easy to access compared with direct spore counting. UN was the only trait for which a doubling of the inoculum pressure level had a significant effect, leading to greater differentiation between genotypes. Consistent with previous studies is the clear relationship between presence of complete resistance against M. larici-populina strain 93ID6 and higher partial resistance to M. larici-populina strain 93CV1 (32% longer LP, 76% smaller UN, and 34% smaller US). In the subpopulation compatible with 93ID6, bimodal distribution of genotypic means for US suggested implication of a major gene inherited from the P. trichocarpa parent. Residual variation was noted for the three epidemiological components, suggesting that additional genes might condition these quantitative traits.

Lack of caregivers limits use of outpatient hematopoietic stem cell transplant program

Our goal was to compare direct and indirect medical costs and quality of life associated with inpatient vs outpatient autologous hematopoietic stem cell transplantation (AuHSCT). Twenty-one sequential outpatients and 26 inpatients were enrolled on this prospective trial. All candidates for AuHSCT were screened for eligibility for outpatient transplantation. Patients with either breast cancer or hematologic malignancy, insurance coverage for the outpatient procedure, one to three caregivers available to provide 24 h coverage, and no significant comorbidities were eligible to participate. Patients without caregivers or insurance coverage for outpatient transplant were accrued to the study in a consecutive manner as inpatient controls, based on willingness to participate in the quality of life portion of the study and to permit review of their hospital and billing records. Approximately half of all 139 prospective outpatient candidates were ineligible because they lacked a caregiver. Most commonly, the patient without a caregiver was single or widowed or their family and friends were needed to provide childcare. Most caregivers were college educated from families with incomes greater than US dollars 80000. Indirect costs to the caregivers totaled a median of US dollars 2520 (range US dollars 684-US dollars 4508), with the majority attributed to lost 'opportunity costs'. Overall, there were significant differences in the total costs of treatment for inpatient vs outpatient AuHSCT (US dollars 40985 vs US dollars 29210, P < 0.01)). In general, no significant differences were detected between inpatient and outpatient scores on quality of life measures. Although significant cost savings were associated with outpatient transplantation, this approach was applicable to only half of our otherwise eligible candidates because of a lack of caregivers. The financial burden associated with the caretaking role may underlie this finding.

F+0 renography in neonates and infants younger than 6 months: an accurate method to diagnose severe obstructive uropathy

We studied the response to F+0 renography and the relative and absolute individual kidney function in neonates and < 6-mo-old infants before and after surgery for unilateral ureteropelvic junction obstruction (UJO).

METHODS

The results obtained at diagnosis and after pyeloplasty for 9 children (8 boys, 1 girl; age range, 0.8-5.9 mo; mean age +/- SD, 2.4 +/- 1.5 mo) with proven unilateral UJO (i.e., affected kidney [AK]) and an unremarkable contralateral kidney (i.e., normal kidney [NK]) were evaluated and compared with a control group of 10 children (6 boys, 4 girls; age range, 0.8-2.8 mo; mean age, 1.5 +/- 0.7 mo) selected because of symmetric renal function, absence of vesicoureteral reflux or infection, and an initially dilated but not obstructed renal pelvis as proven by follow-up. Renography was performed for 20 min after injection of (123)I-hippuran (OIH) (0.5-1.0 MBq/kg) immediately followed by furosemide (1 mg/kg). The relative and absolute renal functions and the response to furosemide were measured on background-subtracted and depth-corrected renograms. The response to furosemide was quantified by an elimination index (EI), defined as the ratio of the 3- to 20-min activities: An EI > or = 3 was considered definitively normal and an EI < or = 1 definitively abnormal. If EI was equivocal (1 < EI < 3), the response to gravity-assisted drainage was used to differentiate AKs from NKs. Absolute separate renal function was measured by an accumulation index (AI), defined as the percentage of (123)I-OIH (%ID) extracted by the kidney 30-90 s after maximal cardiac activity.

RESULTS

All AKs had definitively abnormal EIs at diagnosis (mean, 0.56 +/- 0.12) and were significantly lower than the EIs of the NKs (mean, 3.24 +/- 1.88) and of the 20 control kidneys (mean, 3.81 +/- 1.97; P < 0.001). The EIs of the AKs significantly improved (mean, 2.81 +/- 0.64; P < 0.05) after pyeloplasty. At diagnosis, the AIs of the AKs were significantly lower (mean, 6.31 +/- 2.33 %ID) than the AIs of the NKs (mean, 9.43 +/- 1.12 %ID) and of the control kidneys (mean, 9.05 +/- 1.17 %ID; P < 0.05). The AIs of the AKs increased at follow-up (mean, 7.81 +/- 2.23 %ID) but remained lower than those of the NKs (mean, 10.75 +/- 1.35 %ID; P < 0.05).

CONCLUSION

In neonates and infants younger than 6 mo, (123)I-OIH renography with early furosemide injection (F+0) allowed us to reliably diagnose AKs and to determine if parenchymal function was normal or impaired and if it improved after surgery.

Expansion and long-term culture of differentiated normal rat urothelial cells in vitro

The objective of this study is to establish a reliable cell culture system for the long-term culture of rat urothelial cells (RUC), in which the cells multiply in vitro and form stratified polarized urothelium. Urothelial cells were harvested by the enzymatic digestion of the urothelium exposed by the eversion of resected rat bladders. Primary cultures were initiated in keratinocyte serum-free medium (KSFM) for selective proliferation of urothelial cells. Subsequently, the cells were propagated in a mixture of conditioned medium (CM) derived from Swiss 3T3 cell culture supernatant and KSFM (CM-KSFM). Mean population doubling time was 13.8 +/- 0.9 h. RUC were successfully maintained for 18 passages over a period of 4-5 mo. Detailed investigations of culture conditions showed that CM-KSFM yielded a differentiated multilayer structure. The stratified urothelial sheets measuring 4 x 6 cm2 could be formed and then detached using dispase. Cytokeratin pattern in both the cultured urothelial monolayer and engineered stratified layers was similar to those seen in vivo, as assessed with monoclonal antibody against cytokeratin 17. Ultrastructural morphology showed microvilli, basal cell layer, and desmosomes between adjacent cells in the stratified urothelium.

Prenatal diagnosis of urinary malformations: results in a series of 93 consecutive cases

OBJECTIVE

To evaluate the pertinence of prenatal diagnosis in cases of congenital uropathy.

STUDY DESIGN

Retrospective evaluation over a period of 6.5 years.

METHOD

93 cases were involved in the comparison of prenatal ultrasonographic diagnosis with neonatal findings, autopsy results, and follow-up data.

RESULTS

33 fetuses had renal parenchymal lesions, 44 had excretory system lesions, and 6 had bladder and/or urethral lesions. Seventy-three pregnancies lead to live births. Eighteen terminations of pregnancy were performed on the parents' request for extremely severe malformations. Two intrauterine deaths were observed, and two infants died in the postnatal period. Prenatal diagnosis was obtained at an average of 27 weeks gestation. Diagnostic concordance was excellent in 82% and partial in 12% of cases with renal parenchymal lesions; the false-positive rate was 6%. For excretory system lesions, concordance was excellent in 87% and partial in 7.4% of cases, with a false-positive rate of 5.6%. Finally, concordance was excellent in 100% of cases of bladder and/or urethral lesions. The overall rate of total concordance was 86%. Partial concordance cases consisted of malformations different from those previously diagnosed, but prenatal diagnosis nevertheless lead to further investigations in the neonatal period and to proper management. The false-positive diagnoses (5.4%) never lead to termination of pregnancy.

CONCLUSION

Prenatal diagnosis of congenital uropathy is effective. A third-trimester ultrasonographic examination is necessary to ensure proper neonatal management, considering that the majority of cases are diagnosed at this gestational age.

Prenatal diagnosis of urinary malformations: results in a series of 93 consecutive cases

OBJECTIVE

To evaluate the pertinence of prenatal diagnosis in cases of congenital uropathy.

STUDY DESIGN

Retrospective evaluation over a period of 6.5 years.

METHOD

93 cases were involved in the comparison of prenatal ultrasonographic diagnosis with neonatal findings, autopsy results, and follow-up data.

RESULTS

33 fetuses had renal parenchymal lesions, 44 had excretory system lesions, and 6 had bladder and/or urethral lesions. Seventy-three pregnancies lead to live births. Eighteen terminations of pregnancy were performed on the parents' request for extremely severe malformations. Two intrauterine deaths were observed, and two infants died in the postnatal period. Prenatal diagnosis was obtained at an average of 27 weeks gestation. Diagnostic concordance was excellent in 82% and partial in 12% of cases with renal parenchymal lesions; the false-positive rate was 6%. For excretory system lesions, concordance was excellent in 87% and partial in 7.4% of cases, with a false-positive rate of 5.6%. Finally, concordance was excellent in 100% of cases of bladder and/or urethral lesions. The overall rate of total concordance was 86%. Partial concordance cases consisted of malformations different from those previously diagnosed, but prenatal diagnosis nevertheless lead to further investigations in the neonatal period and to proper management. The false-positive diagnoses (5.4%) never lead to termination of pregnancy.

CONCLUSION

Prenatal diagnosis of congenital uropathy is effective. A third-trimester ultrasonographic examination is necessary to ensure proper neonatal management, considering that the majority of cases are diagnosed at this gestational age.

Differential phosphorylation of tau proteins during kitten brain development and Alzheimer's disease

Differential distribution and phosphorylation of tau proteins were studied in developing kitten brain by using several antibodies, and was compared to phosphorylation in Alzheimer's disease. Several antibodies demonstrated the presence of phosphorylated tau proteins during kitten brain development and identified pathological structures in human brain tissue. Antibody AD2, recognized tau in kittens and adult cats, but reacted in Alzheimer's tissue only with a pathological tau form. Antibody AT8 was prominent in developing kitten neurons and was found in axons and dendrites. After the first postnatal month this phosphorylation type disappeared from axons. Furthermore, dephosphorylation of kitten tau with alkaline phosphatase abolished immunoreactivity of AT8, but not that of AD2, pointing to a protection of the AD2 epitope in cats. Tau proteins during early cat brain development are phosphorylated at several sites that are also phosphorylated in paired helical filaments during Alzheimer's disease. In either event, phosphorylation of tau may play a crucial role to modulate microtubule dynamics, contributing to increased microtubule instability and promoting growth of processes during neuronal development or changing dynamic properties of the cytoskeleton and contributing to the formation of pathological structures in neurodegenerative diseases.

In vitro engineering of human stratified urothelium: analysis of its morphology and function

PURPOSE

Gastric or intestinal patches, commonly used for reconstructive cystoplasty, may induce severe metabolic complications. The use of bladder tissues reconstructed in vitro could avoid these complications. We compared cellular differentiation and permeability characteristics of human native with in vitro cultured stratified urothelium.

MATERIALS AND METHODS

Human stratified urothelium was induced in vitro. Morphology was studied with light and electron microscopy and expression of key cellular proteins was assessed using immunohistochemistry. Permeability coefficients were determined by measuring water, urea, ammonia and proton fluxes across the urothelium.

RESULTS

As in native urothelium the stratified urothelial construct consisted of basal membrane and basal, intermediate and superficial cell layers. The apical membrane of superficial cells formed villi and glycocalices, and tight junctions and desmosomes were developed. Immunohistochemistry showed similarities and differences in the expression of cytokeratins, integrin and cellular adhesion proteins. In the cultured urothelium cytokeratin 20 and integrin subunits alpha6 and beta4 were absent, and symplekin was expressed diffusely in all layers. Uroplakins were clearly expressed in the superficial umbrella cells of the urothelial constructs, however, they were also present in intermediate and basal cells. Symplekin and uroplakins were expressed only in the superficial cells of native bladder tissue. The urothelial constructs showed excellent viability, and functionally their permeabilities for water, urea and ammonia were no different from those measured in native human urothelium. Proton permeability was even lower in the constructs compared to that of native urothelium.

CONCLUSIONS

Although the in vitro cultured human stratified urothelium did not show complete terminal differentiation of its superficial cells, it retained the same barrier characteristics against the principal urine components. These results indicate that such in vitro cultured urothelium, after being grown on a compliant degradable support or in coculture with smooth muscle cells, is suitable for reconstructive cystoplasty.

Coculture of bladder urothelial and smooth muscle cells on small intestinal submucosa: potential applications for tissue engineering technology

PURPOSE

Small intestinal submucosa is a xenogenic, acellular, collagen rich membrane with inherent growth factors that has previously been shown to promote in vivo bladder regeneration. We evaluate in vitro use of small intestinal submucosa to support the individual and combined growth of bladder urothelial cells and smooth muscle cells for potential use in tissue engineering techniques, and in vitro study of the cellular mechanisms involved in bladder regeneration.

MATERIALS AND METHODS

Primary cultures of human bladder urothelial cells and smooth muscle cells were established using standard enzymatic digestion or explant techniques. Cultured cells were then seeded on small intestinal submucosa at a density of 1 x 105 cells per cm.2, incubated and harvested at 3, 7, 14 and 28 days. The 5 separate culture methods evaluated were urothelial cells seeded alone on the mucosal surface of small intestinal submucosa, smooth muscle cells seeded alone on the mucosal surface, layered coculture of smooth muscle cells seeded on the mucosal surface followed by urothelial cells 1 hour later, sandwich coculture of smooth muscle cells seeded on the serosal surface followed by seeding of urothelial cells on the mucosal surface 24 hours later, and mixed coculture of urothelial cells and smooth muscle cells mixed and seeded together on the mucosal surface. Following harvesting at the designated time points small intestinal submucosa cell constructs were formalin fixed and processed for routine histology including Masson trichrome staining. Specific cell growth characteristics were studied with particular attention to cell morphology, cell proliferation and layering, cell sorting, presence of a pseudostratified urothelium and matrix penetrance. To aid in the identification of smooth muscle cells and urothelial cells in the coculture groups, immunohistochemical analysis was performed with antibodies to alpha-smooth muscle actin and cytokeratins AE1/AE3.

RESULTS

Progressive 3-dimensional growth of urothelial cells and smooth muscle cells occurred in vitro on small intestinal submucosa. When seeded alone urothelial cells and smooth muscle cells grew in several layers with minimal to no matrix penetration. In contrast, layered, mixed and sandwich coculture methods demonstrated significant enhancement of smooth muscle cell penetration of the membrane. The layered and sandwich coculture techniques resulted in organized cell sorting, formation of a well-defined pseudostratified urothelium and multilayered smooth muscle cells with enhanced matrix penetration. With the mixed coculture technique there was no evidence of cell sorting although matrix penetrance by the smooth muscle cells was evident. Immunohistochemical studies demonstrated that urothelial cells and smooth muscle cells maintain the expression of the phenotypic markers of differentiation alpha-smooth muscle actin and cytokeratins AE1/AE3.

CONCLUSIONS

Small intestinal submucosa supports the 3-dimensional growth of human bladder cells in vitro. Successful combined growth of bladder cells on small intestinal submucosa with different seeding techniques has important future clinical implications with respect to tissue engineering technology. The results of our study demonstrate that there are important smooth muscle cell-epithelial cell interactions involved in determining the type of in vitro cell growth that occurs on small intestinal submucosa. Small intestinal submucosa is a valuable tool for in vitro study of the cell-cell and cell-matrix interactions that are involved in regeneration and various disease processes of the bladder.

Bioresorbable microspheres by spinning disk atomization as injectable cell carrier: from preparation to in vitro evaluation

Vesico-ureteral reflux, a common pathology in children, can be treated cystoscopically by injection of a bulking material underneath the most distal, intramural ureter, which forces the latter to do a detour, increasing its submucosal path. This increase of the length of the submucosal path of the ureter within the bladder is directly responsible for the anti-reflux effect. So far Teflon and collagen paste have been commonly used as bulking materials. We suggest replacing these materials by living tissue consisting of bladder smooth muscle, normally present at this location. The aim of this work is to provide a long-term effective treatment by producing bioresorbable microspheres which can act as a support matrix and an entrapment substance for bladder smooth muscle cells, with the goal of an in vivo transfer of the in vitro cultured cells with a minimal surgical procedure. By the use of Spinning Disk Atomization, which has specifically been developed for this purpose, we have shown two methods for the preparation of porous poly(lactic acid) microspheres with tunable sizes from 160 to 320 microm. The controlled solvent burst method has shown the advantage over the crystal leaching method in the direct creation of microspheres with large closed pores, by atomizing the polymer solution in controlled temperature conditions. Microspheres with various closed pore structures have thus been prepared. The innovation of this work is in the direct and rapid formation of porous microspheres with a pore morphology which is designed to create cavities suitable for adherence and growth of cells by adapting the temperature conditions of atomization. Injection tests have shown promising results in using these cell-loaded microspheres for future non-invasive tissue engineering.

Studies on the in vitro assembly of a beta 1-40: implications for the search for a beta fibril formation inhibitors

The progressive deposition of the amyloid beta peptide (Abeta) in fibrillar form is a key feature in the development of the pathology in Alzheimer's disease (AD). We have characterized the time course of Abeta fibril formation using a variety of assays and under different experimental conditions. We describe in detail the morphological development of the Abeta polymerization process from pseudo-spherical structures and protofibrils to mature thioflavin-T-positive/Congo red-positive amyloid fibrils. Moreover, we structurally characterize the various polymorphic fibrillar assemblies using transmission electron microscopy and determine their mass using scanning transmission electron microscopy. These results provide the framework for future investigations into how target compounds may interfere with the polymerization process. Such substances might have a therapeutic potential in AD.

Amyloid fibril formation from full-length and fragments of amylin

Amyloiddeposits of fibrillar human amylin (hA) in the pancreas may be a causative factor in type-2 diabetes. A detailed comparison of in vitro fibril formation by full-length hA(1-37) versus fragments of this peptide-hA(8-37) and hA(20-29)-is presented. Circular dichroism spectroscopy revealed that fibril formation was accompanied by a conformational change: random coil to beta-sheet/alpha-helical structure. Fibril morphologies were visualized by electron microscopy and displayed a remarkable diversity. hA(20-29) formed flat ribbons consisting of numerous 3. 6-nm-wide protofibrils. In contrast, hA(1-37) and hA(8-37) formed polymorphic higher order fibrils by lateral association and/or coiling together of 5.0-nm-wide protofibril subunits. For full-length hA(1-37), the predominant fibril type contained three protofibrils and for hA(8-37), the predominant type contained two protofibrils. Polymerization was also monitored with the thioflavin-T binding assay, which revealed different kinetics of assembly for hA(1-37) and hA(8-37) fibrils. hA(20-29) fibrils did not bind thioflavin-T. Together the results demonstrate that the N-terminal region of the hA peptide influences the relative frequencies of the various higher order fibril types and thereby the overall kinetics of fibril formation. Furthermore, while residues 20-29 contribute to the fibrils' beta-sheet core, the flanking C- and N-terminal regions of the hA peptide determine the interactions involved in the formation of higher order coiled polymorphic superstructures.

The hrpB and hrpG regulatory genes of Ralstonia solanacearum are required for different stages of the tomato root infection process

hrp genes, encoding type III secretion machinery, have been shown to be key determinants for pathogenicity in the vascular phytopathogenic bacterium Ralstonia solanacearum GMI1000. Here, we show phenotypes of R. solanacearum mutant strains disrupted in the prhJ, hrpG, or hrpB regulatory genes with respect to root infection and vascular colonization in tomato plants. Tests of bacterial colonization and enumeration in tomato plants, together with microscopic observations of tomato root sections, revealed that these strains display different phenotypes in planta. The phenotype of a prhJ mutant resembles that of the wild-type strain. An hrpB mutant shows reduced infection, colonization, and multiplication ability in planta, and induces a defense reaction similar to a vascular hypersensitive response at one protoxylem pole of invaded plants. In contrast, the hrpG mutant exhibited a wild-type level of infection at secondary root axils, but the ability of the infecting bacteria to penetrate into the vascular cylinder was significantly impaired. This indicates that bacterial multiplication at root infection sites and transit through the endodermis constitute critical stages in the infection process, in which hrpB and hrpG genes are involved. Moreover, our results suggest that the hrpG gene might control, in addition to hrp genes, other functions required for vascular colonization.

ELISA-quantitation of phosphorylated tau protein in the Alzheimer's disease brain

A reliable, sensitive and specific sandwich ELISA for the quantitation of paired helical filament (PHF) tau in human brain was developed using well-defined monoclonal antibodies. We examined rapid-autopsy-derived brain tissue from 21 neuropathologically confirmed Alzheimer's disease (AD) patients and 14 nondemented controls, matched for age, sex and postmortem delay times. We demonstrated significant elevations of phosphorylated tau levels in the frontal and parietal cortex as well as in the hippocampus of AD patients as compared to the nondemented controls. No difference was observed in the cerebellum. Phosphorylated tau levels measured by ELISA were significantly correlated with the presence or absence of neurofibrillary tangles.

[Don't let it get that far! Tips and tricks for prevention of decubitus ulcer and therapy in general practice]

Successful prevention and treatment of decubitus ulcer requires a high level of skill and competence on the part of the diverse professional groups involved in providing nursing care and medical treatment. Pressure relief can be achieved in a variety of ways, and the needs of the patients must be integrated in the approach adopted. Constant inspection and care of the skin, and promotion of patient movement/activity, coupled with familiarity with the latest information on wound and pain management are the prerequisites for appropriate treatment. A reduction of the problem to the use of special mattresses and beds must be avoided.