Cloning and molecular and immunological characterisation of two new food allergens, Cap a 2 and Lyc e 1, profilins from bell pepper (Capsicum annuum) and Tomato (Lycopersicon esculentum)

BACKGROUND

Profilins are recognised by IgE of about 20% of patients allergic to birch pollen and plant foods. They are ubiquitous intracellular proteins highly cross-reactive among plant species. Therefore, they were called panallergens and are made responsible for cross-sensitisation between plant pollen and food.

OBJECTIVES

The aim of the present study was to clone the cDNAs encoding profilins from bell pepper and tomato, to produce and purify the recombinant proteins and to compare their IgE-binding capacities to those of the natural proteins.

METHODS

cDNA clones coding for profilin were obtained by RT-PCR from total RNA of tomato and bell pepper fruits, sequenced and expressed as non-fusion proteins in ESCHERICHIA COLI. The recombinant profilins were subsequently purified and tested for IgE-binding and inhibition capacity with sera from 34 food-allergic patients. Possible oligomerisation of recombinant profilins was investigated by HPLC analysis and its influence on IgE binding assayed by ELISA.

RESULTS

The open reading frame from both profilins encompasses 393 bp with a predicted molecular mass of 14,184 kD and a pI of 4.44 for bell pepper profilin (Cap a 2) and 14,257 kD and a pI of 4.46 for the profilin from tomato (Lyc e 1). The two protein sequences display 91% identity, whereas tomato profilin from pollen shares only 75% identity with tomato fruit profilin. Eleven out of 34 food-allergic patients (32%) display IgE binding to both purified profilins. Preincubation of a serum pool with either purified rCap a 2 or rLyc e 1 nearly abolished IgE binding to natural Cap a 2 and Lyc e 1, respectively. In addition, purified recombinant Cap a 2 was able to inhibit IgE-binding to rLyc e 1 by approximately 50%, whereas rLyc e 1 completely blocked IgE-binding to rCap a 2 in cross-inhibition assays. HPLC analysis showed that in solution Cap a 2 and Lyc e 1 can be found predominantly as dimers, which can be partially reduced to monomers by addition of dithiothreitol (DTT). In ELISA DTT-treated Lyc e 1 displayed a clearly lower IgE-binding capacity than untreated profilin.

CONCLUSIONS

Purified rCap a 2 and rLyc e 1 proved to be valuable tools for studying cross-reactivity to profilins in patients allergic to pollen and food.

Scanning near-field optical microscopy of a cell membrane in liquid

The applications of scanning near-field optical microscopy to biological specimens under physiological conditions have so far been very rare since common techniques for a probe-sample distance control are not as well suited for operation in liquid as under ambient conditions. We have shown previously that our own approach for a distance control, based on a short aperture fibre probe and a tuning fork as force sensor in a tapping mode, works well even on soft material in water. By means of an electronic self-excitation circuit, which compensates for changes of the resonance frequency due to evaporation of liquid, the stability of the force feedback has now been further improved. We present further evidence for the excellent suitability of the tapping-mode-like distance control to an operation in liquid, for example, by force-imaging of double-stranded DNA. Moreover, we demonstrate that a nuclear envelope in liquid can be imaged with a high optical resolution of approximately 70 nm without affecting its structural integrity. Thereby, single nuclear pores in the nuclear envelope with a nearest neighbour distance of approximately 120 nm have been optically resolved for the first time.

SAP and partners: IS-H and IS-H* MED

OBJECTIVES

The Styrian Hospital Organization with 21 hospitals including the Graz University Hospital, and the Heidelberg University Hospital implemented a new HIS based on SAP/R3, ISH, ISH* MED with the objective to have an integrated system to support patient administration and management, patient care, clinical documentation, research etc.

METHODS

Heidelberg University Hospital chose a step by step method for the introduction of the system, beginning with patient administration (ISH) and proceeding with clinical functions (ISH* MED). In Styria, the full functionality was implemented--as part of the selection process--in one peripheral hospital and in the Ear, Nose and Throat (ENT) Department of the Graz University Hospital, including special documents to support the processes in the highly specialized ENTunits.

RESULTS AND CONCLUSIONS

The standard modules are performant, stable and basically well accepted. Particularly in Graz, it has been shown that the requirements of highly specialized departments for work flow management, documentation and integration of subsystems and data from different sources can be fulfilled by special documents and programs--although at the expense of additional workload particularly in the initial phases of such a project.

Photonic nanopatterns of gold nanostructures indicate the excitation of surface plasmon modes of a wavelength of 50-100 nm by scanning near-field optical microscopy

Scanning near-field optical microscopy images of metal nanostructures taken with the tetrahedral tip (T-tip) show a distribution of dark and bright spots at distances in the order of 25-50 nm. The images are interpreted as photonic nanopatterns defined as calculated scanning near-field optical microscopy images using a dipole serving as a light-emitting scanning near-field optical microscopy probe. Changing from a positive to a negative value of the dielectric function of a sample leads to the partition of one spot into several spots in the photonic nanopatterns, indicating the excitation of surface plasmons of a wavelength in the order of 50-100 nm in metal nanostructures.

Enhanced light confinement in a near-field optical probe with a triangular aperture

We present a probe concept for scanning near-field optical microscopy combining the excellent background suppression of aperture probes with the superior light confinement of apertureless probes. A triangular aperture at the tip of a tetrahedral waveguide (full taper angle approximately 90 degrees ) shows a strong field enhancement at only one rim when illuminated with light of suitable polarization. Compared to a circular aperture of equivalent size, the resolution capability is doubled without loss of brightness. For a approximately 60 nm sized triangular aperture, we measured an optical resolution <40 nm and a transmission of approximately 10(-4).

High-power femtosecond Yb-doped fiber amplifier

We report on the generation of linearly chirped parabolic pulses with 17-W average power at 75 MHz repetition rate and diffraction-limited beam quality in a large-mode-area ytterbium-doped fiber amplifier. Highly efficient transmission gratings in fused silica are applied to recompress these pulses down to 80-fs with an efficiency of 60%, resulting in a peak power of 1.7 MW. Power scaling limitations given by the amplifier bandwidth are discussed.

[Percutaneous vertebroplasty]

PURPOSE

To describe the procedure of percutaneous vertebroplasty and to present our first clinical results of patients treated for benign or malignant painful vertebral body disease.

MATERIAL AND METHODS

We performed percutaneous vertebroplasty in 31 painful lesions of the spine. Liquid bone cement was injected into the affected vertebral body using fluoroscopic guidance through a bilateral transpedicular approach. Etiology of the bone disease was assessed by biopsy. Pain intensity was assessed before and 1 week after the procedure by standardized catalogue.

RESULTS

Percutaneous vertebroplasty was performed in 17 thoracic and in 14 lumbar spine bodies of benign (n = 23) or malignant (n = 8) disease; no clinically relevant complications occurred. All patients reported significant pain relief 1 week after the intervention. One week after treatment, patients were pain-free in 15/31 vertebral bodies, and reported mild residual pain not necessitating narcotic medication in 16/31 cases.

CONCLUSION

In accordance with the literature, percutaneous vertebroplasty proved to be a highly effective, minimal invasive interventional procedure to treat severely painful bone lesions of benign and malignant origin.

Spectral properties of fluctuating electromagnetic fields in a plane cavity: implication for nanoscale physics

Spectral power densities of fluctuating electromagnetic fields and their spatial derivatives of all orders in any point of a transparent plane gap between two media described by different complex permittivities and by different temperatures were derived on a basis of generalized Kirchhoff's law. Electromagnetic losses into the two absorbing media induced by a field of a point dipole or of point multipolelike origins situated in any place of interest at the transparent gap were determined. The corresponding electrodynamical regular Green problem for a point dipole and for point multipoles of any orders constituted by the point dipole was solved. We demonstrate ways to obtain different asymptotic cases following from our general solution including the problem for a half space, Planck's formula for black body radiation, the van der Waals forces for solids kept at different temperatures, and contributions from propagating and evanescent waves. Expressions for electromagnetic loss of a point multipole of any order in selected geometry of the problem were derived and, as an important limiting case related to problems of near field microscopy, when the multipole is situated over a half space.

MedRapid--medical community & business intelligence system

OBJECTIVE

currently, it takes at least 6 months for researchers to communicate their results. This delay is caused (a) by partial lacks of machine support for both representation as well as communication and (b) by media breaks during the communication process.

METHODS

To make an integrated communication between researchers and practitioners possible, a general structure for medical content representation has been set up. The procedure for data entry and quality management has been generalized and implemented in a web-based authoring system.

RESULTS

The MedRapid-system supports the medical experts in entering their knowledge into a database. Here, the level of detail is still below that of current medical guidelines representation. However, the symmetric structure for an area-wide medical knowledge representation is highly retrievable and thus can quickly be communicated into daily routine for the improvement of the treatment quality. In addition, other sources like journal articles and medical guidelines can be references within the MedRapid-system and thus be communicated into daily routine.

CONCLUSIONS

The fundamental system for the representation of medical reference knowledge (from reference works/books) itself is not sufficient for the friction-less communication amongst medical staff. Rather, the process of (a) representing medical knowledge, (b) refereeing the represented knowledge, (c) communicating the represented knowledge, and (d) retrieving the represented knowledge has to be unified. MedRapid will soon support the whole process on one server system.

Clinical outcome differences for lipomyelomeningoceles, intraspinal lipomas, and lipomas of the filum terminale

Failure to differentiate between the different types of lumbosacral lipomas may lead to inaccurate assumptions and inappropriate management of patients. The goal of this study was to determine whether there is a difference in clinical outcome between patients with lipomyelomeningocles, intraspinal lipomas, and lipomas of the filum terminale. One hundred and fourteen patients with spinal dysraphism were seen at Duke University Medical Center between 1995-1999. All patients who had undergone previous operative intervention for these lesions were excluded. Twenty-two patients with intradural lipomas were identified. Of these, 14 (64%) had lipomyelomeningoceles and 8 (36%) had intraspinal lipomas. Twenty-five patients had filum terminale lipomas. Operative management consisted of lumbosacral laminectomies with microsurgical resection of the lipoma and division of the fatty filum. Average age at presentation in symptomatic patients with lipomas of the filum terminale was 17.7 years, and 23 years in the symptomatic intraspinal lipoma group. Patients with lipomyelomeningoceles ranged in age from 1 day to 18 years, with the majority being younger than 2 years. After an average follow-up of 8 months all patients showed improvement in motor strength following operative intervention. Greater improvements in sensory, bladder, and pain scores were associated with filum terminale lipomas. The least improvements in these categories were seen in the lipomyelomeningocele group. Motor strength is the most likely deficit to improve following operative intervention. Lipomyelomeningoceles, intraspinal lipomas, and filum termniale lipomas have different clinical outcomes following operative intervention.

Characterization of a mutation in the lens-specific MP70 encoding gene of the mouse leading to a dominant cataract

During an ethylnitrosourea mutagenesis screen, Aey5, a new mouse mutation exhibiting an autosomal dominant congenital cataract was isolated. The cataractous phenotype is visible at the eye opening and progresses to a nuclear and zonular cataract at 2 months of age with no difference in onset or severity between heterozygous and homozygous mutants. Histological analysis revealed that fiber cell differentiation continues at the lens bow region, but the cell nuclei do not degrade normally and remain in the deeper cortex. Further, the lens nucleus has clefts of various sizes while the remainder of the eye was morphologically normal. The mutation was mapped to chromosome 3 between the markers D3Mit101 and D3Mit77 near the connexin encoding genes Gja5 and Gja8. Sequence analysis revealed no differences in the Gja5 gene, but identified a T-->C mutation at position 191 in the Gja8 gene, which was confirmed by an additional Mva 12691 restriction site in the genomic DNA of homozygous mutants. This mutation results in Val-->Ala substitution at codon 64 of connexin50 (Cx50) also known as lens membrane protein 70 (MP70). Aey5 represents the second dominant mouse cataract mutant affecting Cx50, a membrane protein preferentially expressed in the lens. Since both mutations affect similar regions in the first extracellular domain this region appears to be critically important for its function in lens transparency.

Characterization of a new, dominant V124E mutation in the mouse alphaA-crystallin-encoding gene

PURPOSE

During an ethylnitrosourea (ENU) mutagenesis screening, mice were tested for the occurrence of dominant cataracts. The purpose of the study was morphologic description, mapping of the mutant gene, and characterization of the underlying molecular lesion in a particular mutant, Aey7.

METHODS

Isolated lenses were photographed and histologic sections of the eye were analyzed according to standard procedures. Linkage analysis was performed with a set of microsatellite markers covering all autosomal chromosomes. cDNA was amplified after reverse transcription of lens mRNA. For PCR, cDNA or genomic DNA was used as a template.

RESULTS

Nuclear opacity and posterior suture anomaly were visible at eye opening and progressed to a nuclear and zonular cataract at 2 months of age. The opacity as well as the microphthalmia was more pronounced in the homozygotes than in the heterozygotes. The mutation was mapped to chromosome 17 between the markers D17Mit133 and D17Mit180. This position made the alphaA-crystallin-encoding gene (Cryaa) an excellent candidate gene. Sequence analysis revealed a mutation of a T to an A at position 371 in the Cryaa cDNA. The mutation was confirmed by an additional MnlI restriction site in the genomic DNA of homozygous mutants leading to replacement of Val with Glu at codon 124 affecting the C-terminal region of the alphaA-crystallin.

CONCLUSIONS

The Aey7 mutant represents the first dominant mouse cataract mutation affecting the Cryaa gene. The mutation leads to progressive opacification of the lens. Compared with the beta- and gamma-crystallin-encoding genes, mutations in the alpha-crystallin-encoding genes are rare.

The result of equilibrium-constant calculations strongly depends on the evaluation method used and on the type of experimental errors

The determination of equilibrium constants is a widespread tool both to understand and to characterize protein-protein interactions. A variety of different methods, among them Scatchard analysis, is used to calculate these constants. Although more than 1000 articles dealing with equilibrium constants are published every year, the effects of experimental errors on the results are often disregarded when interpreting the data. In the present study we theoretically analysed the effect of various types of experimental errors on equilibrium constants derived by three different methods. A computer simulation clearly showed that certain experimental errors, namely inaccurate background correction, inexact calibration, saturation effects, slow kinetics and simple scattering, can adversely affect the result. The analysis further revealed that, for a given type of error, the same data set can produce different results depending on the method used.

Two configurations of static magnetic fields for treating rheumatoid arthritis of the knee: a double-blind clinical trial

OBJECTIVE

To assess the efficacy of a nonpharmacologic, noninvasive static magnetic device as adjunctive therapy for knee pain in patients with rheumatoid arthritis (RA).

DESIGN

Randomized, double-blind, controlled, multisite clinical trial.

SETTING

An American and a Japanese academic medical center as well as 4 community rheumatology and orthopedics practices.

PATIENTS

Cohort of 64 patients over age 18 years with rheumatoid arthritis and persistent knee pain, rated greater than 40/100mm, despite appropriate use of medications.

INTERVENTION

Four blinded MagnaBloc (with 4 steep field gradients) or control devices (with 1 steep field gradient) were taped to a knee of each subject for 1 week.

MAIN OUTCOME MEASURES

The American College of Rheumatology recommended core set of disease activity measures for RA clinical trials and subjects' assessment of treatment outcome.

RESULTS

Subjects randomly assigned to the MagnaBloc (n = 38) and control treatment groups (n = 26) reported baseline pain levels of 63/100mm and 61/100mm, respectively. A greater reduction in reported pain in the MagnaBloc group was sustained through the 1-week follow-up (40.4% vs 25.9%) and corroborated by twice daily pain diary results (p < .0001 for each vs baseline). However, comparison between the 2 groups demonstrated a statistically insignificant difference (p < .23). Subjects in the MagnaBloc group reported an average decrease in their global assessment of disease activity of 33% over 1 week, as compared with a 2% decline in the control group (p < .01). After 1 week, 68% of the MagnaBloc treatment group reported feeling better or much better, compared with 27% of the control group, and 29% and 65%, respectively, reported feeling the same as before treatment (p < .01).

CONCLUSIONS

Both devices demonstrated statistically significant pain reduction in comparison to baseline, with concordance across multiple indices. However, a significant difference was not observed between the 2 treatment groups (p < .23). In future studies, the MagnaBloc treatment should be compared with a nonmagnetic placebo treatment to characterize further its therapeutic potential for treating RA. This study did elucidate methods for conducting clinical trials with magnetic devices.

Determination of optimal non-denaturing elution conditions from affinity columns by a solid-phase screen

The purification of biological macromolecules by affinity chromatography is a widespread technique used to separate a protein from other biological components. However, this method may destroy the protein's physiological activity because elution conditions aimed to dissociate the protein of interest from the high-affinity matrix often irreversibly denature it. In the present work, we have developed a solid-phase assay to determine the optimal elution conditions for any buffer (in two steps) by determining (i) the lowest buffer concentration yielding maximum dissociation from the immobilized component and (ii) the highest buffer concentration that can be used without the loss of the protein's binding activity. Any buffer that can be reasonably used between these defined concentrations is suitable for elution within this interval. The screen is easily performed within a few hours and only requires nanograms to a few micrograms of protein. As an example, we demonstrate that more than 95% of the human transferrin receptor bound to a transferrin-sepharose ligand affinity column can be eluted with full binding activity at KSCN concentrations between 232 and 414 nM, whereas elution with urea is not suitable to purify fully functional protein.

Development of a novel molecular adapter for the optimization of immunotoxins

Immunotoxins consisting of catalytic domains of natural toxins and tumor-specific ligands were modified by introducing a molecular adapter that is able to transport the toxic domain more efficiently into cells. The adapter is a three-component structure: its core is a membrane transfer sequence (MTS) flanked by two different cleavable sequences. The directed and irreversible cellular uptake of the construct is driven by either enzymatic or chemical cleavage of the two flanking sequences. In our studies, the purified A-chain of diphtheria toxin (DT) was coupled to two different MTSs via disulfide bonds. A cytotoxicity assay revealed that the constructs containing the MTSs were more potent than DT A-chain alone and that the disulfide bond was cleaved.

Real-time anatomical 3D image extraction for laparoscopic surgery

Progress in the application of augmented reality to laparoscopic surgery has been limited by the difficulty associated with generating geometric information about the current patient in real time. Structured light techniques are well known methods for generating range images using a camera and projector, but typically fail when faced with biological specimens. We describe techniques and equipment that have shown promise for acquisition of range images for use in a real-time augmented reality system for laparoscopic surgery.

Aey2, a new mutation in the betaB2-crystallin-encoding gene of the mouse

PURPOSE

During an ethylnitrosourea (ENU) mutagenesis screen, mice were tested for the occurrence of dominant cataracts. One particular mutant was found that caused progressive opacity and was referred to as Aey2. The purpose of the study was to provide a morphologic description, to map the mutant gene, and to characterize the underlying molecular lesion.

METHODS

Isolated lenses were photographed, and histologic sections of the eye were analyzed according to standard procedures. Linkage analysis was performed using a set of microsatellite markers covering all autosomal chromosomes. cDNA from candidate genes was amplified after reverse transcription of lens mRNA.

RESULTS

The cortical opacification visible at eye opening progressed to an anterior suture cataract and reached its final phenotype as total opacity at 8 weeks of age. There was no obvious difference between heterozygous and homozygous mutants. The mutation was mapped to chromosome 5 proximal to the marker D5Mit138 (8.7 +/- 4.2 centimorgan [cM]) and distal to D5Mit15 (12.8 +/- 5.4 cM). No recombinations were observed to the markers D5Mit10 and D5Mit25. This position makes the genes within the betaA4/betaB-crystallin gene cluster excellent candidate genes. Sequence analysis revealed a mutation of T-->A at position 553 in the Crybb2 gene, leading to an exchange of Val for GLU: It affects the same region of the Crybb2 gene as in the Philly mouse. Correspondingly, the loss of the fourth Greek key motif is to be expected.

CONCLUSIONS

The Aey2 mutant represents the second allele of Crybb2 in mice. Because an increasing number of beta- and gamma-crystallin mutations have been reported, a detailed phenotype-genotype correlation will allow a clearer functional understanding of beta- and gamma-crystallins.

Oral mucositis and the clinical and economic outcomes of hematopoietic stem-cell transplantation

PURPOSE

To explore the relationship between oral mucositis and selected clinical and economic outcomes in blood and marrow transplant patients.

PATIENTS AND METHODS

Subjects consisted of 92 transplant patients from eight centers who participated in a multinational pilot study of a new oral mucositis scoring system (Oral Mucositis Assessment Scale [OMAS]). In the pilot study, patients were evaluated for erythema and ulceration/pseudomembrane formation beginning on the first day of conditioning and continuing for 28 days. We examined the relationship between patients' peak OMAS scores and days with fever (body temperature > 38.0 degrees C), the occurrence of significant infection, days of total parenteral nutrition (TPN), and days of injectable narcotic therapy (all over 28 days), days in hospital (over 60 days), total hospital charges for the index admission, and vital status at 100 days.

RESULTS

Patients' peak OMAS scores spanned the full range of possible values (0 to 5) and were significantly (P <.05) correlated with all of the outcomes of interest except days with fever (P =.21). In analyses controlling for type of graft (autologous v allogeneic) and study center, a 1-point increase in peak OMAS score was associated with (1) 1.0 additional day with fever (P <.01), (2) a 2.1-fold increase in risk of significant infection (P <.01), (3) 2.7 additional days of TPN (P <.0001), (4) 2.6 additional days of injectable narcotic therapy (P <.0001), (5) 2.6 additional days in hospital (P <.01), (6) $25,405 in additional hospital charges (P <.0001), and (7) a 3.9-fold increase in 100-day mortality risk (P <.01). Mean hospital charges were $42,749 higher among patients with evidence of ulceration compared with those without (P =.06).

CONCLUSION

Oral mucositis is associated with significantly worse clinical and economic outcomes in blood and marrow transplantation.