Astrochemical relevance of VUV ionization of large PAH cations.

CONTEXT: As a part of interstellar dust, polycyclic aromatic hydrocarbons (PAHs) are processed by the interaction with vacuum ultra-violet (VUV) photons that are emitted by hot young stars. This interaction leads to the emission of the well-known aromatic infrared bands but also of electrons, which can significantly contribute to the heating of the interstellar gas. AIMS: Our aim is to investigate the impact of molecular size on the photoionization properties of cationic PAHs. METHODS: Trapped PAH cations of sizes between 30 and 48 carbon atoms were submitted to VUV photons in the range of 9 to 20 eV from the DESIRS beamline at the synchrotron SOLEIL. All resulting photoproducts including dications and fragment cations were mass-analyzed and recorded as a function of photon energy. RESULTS: Photoionization is found to be predominant over dissociation at all energies, which differs from an earlier study on smaller PAHs. The photoionization branching ratio reaches 0.98 at 20 eV for the largest studied PAH. The photoionization threshold is observed to be between 9.1 and 10.2 eV, in agreement with the evolution of the ionization potential with size. Ionization cross sections were indirectly obtained and photoionization yields extracted from their ratio with theoretical photoabsorption cross sections, which were calculated using time-dependent density functional theory. An analytical function was derived to calculate this yield for a given molecular size. CONCLUSIONS: Large PAH cations could be efficiently ionized in H i regions and provide a contribution to the heating of the gas by photoelectric effect. Also, at the border of or in H ii regions, PAHs could be exposed to photons of energy higher than 13.6 eV. Our work provides recipes to be used in astronomical models to quantify these points.

[Which colours can we hear?: light stimulation of the hearing system]. / Welche Farben könnten wir hören?: Lichtstimulation des Hörsystems.

The success of conventional hearing aids and electrical auditory prostheses for hearing impaired patients is still limited in noisy environments and for sounds more complex than speech (e. g. music). This is partially due to the difficulty of frequency-specific activation of the auditory system using these devices. Stimulation of the auditory system using light pulses represents an alternative to mechanical and electrical stimulation. Light is a source of energy that can be very exactly focused and applied with little scattering, thus offering perspectives for optimal activation of the auditory system. Studies investigating light stimulation of sectors along the auditory pathway have shown stimulation of the auditory system is possible using light pulses. However, further studies and developments are needed before a new generation of light stimulation-based auditory prostheses can be made available for clinical application.

Intestinal alpha-defensin expression in pediatric inflammatory bowel disease.

BACKGROUND: Reduced alpha-defensin expression has been reported in the terminal ileum (TI) of adult patients with ileal Crohn's disease (CD). However, little is known about alpha-defensin expression in children with chronic inflammatory bowel disease (IBD). METHODS: In all, 283 intestinal biopsies were obtained from children with CD, ulcerative colitis (UC), and healthy controls. Absolute mRNA copy numbers for HD5, HD6, IL-8, Villin 1, and Tcf-4 were analyzed by reverse-transcription polymerase chain reaction (RT-PCR). HD5 immunostaining was performed on biopsy sections and patients genotyped for NOD2 mutations. RESULTS: Equal expression levels of alpha-defensins (HD5 and HD6) were found in TI biopsies of children with ileal CD (L1+L3) compared to patients with colonic disease (L2) and healthy controls. In contrast, we found significantly higher levels of alpha-defensins in the TI of children with UC compared to CD and controls. Reduced expression of Tcf-4 was observed exclusively in the duodenum and TI of CD patients with L1+L3 phenotype. We demonstrate significantly increased expression of HD5 and HD6 in the inflamed colon of IBD children (UC and CD) attributable to the presence of metaplastic Paneth cells. CONCLUSIONS: In this study no difference in alpha-defensin expression was found in the TI of CD children and controls. However, significant reduction of Tcf-4 in L1+L3 phenotype suggests that a possibly impaired PC differentiation may lead to altered HD5 and HD6 expression at some stage of disease. Additionally, substantially increased expression of alpha-defensins in the inflamed colonic mucosa of children with IBD raises the question for their potential involvement in modulating inflammation in these patients.

In vitro stimulation and expansion of human tumour-reactive CD8+ cytotoxic T lymphocytes by anti-CD3/CD28/CD137 magnetic beads.

Adoptive immunotherapy with tumour-reactive CD8(+) cytotoxic T lymphocytes (CTLs) requires efficient in vitro approaches allowing the expansion of CTLs to large numbers prior infusion. Here, we investigated the antigen-independent activation and the expansion of human T cells in peripheral blood mononuclear cells (PBMCs) and in tumour-reactive CTLs using Dynabeads coated with monoclonal antibodies to CD3 and to the costimulatory molecules CD28 and CD137 (4-1BB). T cells in PBMCs showed an increased expansion rate of 15- to 17-fold during a 2-week culture period using antibody-conjugated beads with interleukin-2 (IL-2) added versus IL-2 alone. No significant difference between CD3/CD28 beads and CD3/CD28/CD137 beads was observed (P = 0.4). In contrast, expansion of tumour-reactive CD8(+) CTLs over 2 weeks was more efficient using CD3/CD28/CD137 beads (14.4-fold ± 1.2) compared with CD3/CD28 beads (10.6-fold ± 0.7) (P = 0.03) and matched well to the control arm using weekly stimulation with tumour cells. Although all modes of in vitro stimulation decreased the expression of central memory markers CD62L and CCR7 on CTLs, bead-activated cultures expressed consistently higher levels than tumour-stimulated cultures. CTLs analysed after bead-induced expansion versus weekly tumour stimulation showed equal IFN-γ production in ELISPOT assay. Furthermore, cytotoxicity assays demonstrated an either unchanged or slightly reduced capability of tumour cell lysis for antigen-independent stimulated CTLs versus those that maintained on weekly tumour stimulation, regardless of which type of beads was used. Our data suggest that the conjugation of anti-CD137 antibodies to conventional CD3/CD28 beads results in a minor but significant increase in the expansion capacity for tumour-reactive CD8(+) CTLs.

Chromosomal location and molecular mapping of a tan spot resistance gene in the winter wheat cultivar Red Chief.

The winter wheat cultivar Red Chief has been identified as the wheat cultivar most resistant to Pyrenophora tritici-repentis (Ptr). This study was undertaken to determine the inheritance, chromosomal location and molecular mapping of a tan spot resistance gene in Red Chief. χ² analysis of the F2 segregation data of the hybrids between 21 monosomic lines of the susceptible wheat cultivar Chinese Spring and the resistant cultivar Red Chief revealed that tan spot resistance in cv. Red Chief is controlled by a single recessive gene located on chromosome 3A. Linkage analysis using SSR markers in the Red Chief/Chinese Spring F2 population showed that the tsr4 gene is clustered in the region around Xgwm2a, on the short arm of chromosome 3A. This marker has also been identified as the closest marker to the tsr3 locus on chromosome 3D in synthetic wheat lines. Validation analysis of this marker for the tsr3 and tsr4 genes using 28 resistant and 6 susceptible genotypes indicated that the 120 bp allele (the tsr3 gene) specific fragment was observed in 11 resistant genotypes, including the three synthetic lines XX41, XX45 and XX110, while the 130 bp allele was amplified only in cv. Red Chief and Dashen. Xgwm2a can be used to trace the presence of the target gene in successive backcross generations and pyramiding of the tsr3 & tsr4 genes into a commonly grown and adaptable cultivar.

Optoacoustic induced vibrations within the inner ear.

An acoustic transient can be generated inside an absorbing tissue as a result of laser-tissue interaction after pulsed laser irradiation. Herein we report a novel application of this physical process, the optoacoustic wave generation in the inner ear and subsequently the induction of basilar membrane vibrations. These laser induced vibrations show a direct correlation to the laser energy and an indirect correlation to the distance from the irradiation focus. Through these characteristics they may be used, in a new generation of cochlear implants, to improve the frequency specific cochlear activation and consequently improve speech perception in hearing impaired patients with residual hearing.

[Characteristics of several humidifiers for CPAP-therapy, invasive and non-invasive ventilation and oxygen therapy under standardised climatic conditions in a climatic chamber]. / Charakteristik mehrerer Befeuchter für die CPAP- sowie invasive und nicht invasive Beatmungstherapie und Sauerstofflangzeittherapie unter standardisierten Bedingungen in einer Klimakammer.

INTRODUCTION: Patients receiving mechanical ventilation and oxygen therapy frequently complain about the dryness of their airways. Humidifiers increase air humidity by generating water vapour and thus preventing the mucosa from desiccation. In this bench study, we compared the efficiency of several humidifiers. METHODS: Two identical humidifiers of each type (HC 602, HumiCare 200, Humid Aire 2i, minni-Max, MR 730 AGM, REMstar, Sirius, Somnia2, Somno Comfort2, VENTIclick, VIVO 30) were measured at three different heating intensities (low, medium, high) and three different flow rates (20, 55 and 90 l/min). The relative humidity at the exit of the tube and the temperature of the water in the heating chamber were registered. Additionally, we measured the humidity of the oxygen humidifier Respiflo at 1 - 5 l/min, the Respiflo was filled with either NaCl 0.9% or Aqua dest. Measurements were taken in a climatic chamber at 20 degrees C and 50% relative humidity. The atmospheric pressure was taken into consideration. RESULTS: The MR 730 AGM and Humicare 200 generated a constant relative humidity of 100%. Among the remaining humidifiers, only the HC 602, HumidAire 2i and REMstar reached a humidity of about 95% at high flow rates. The Minni-Max, Somnia2 and VIVO 30 generated a humidity of 95% still at a flow rate of 55 l/min. The Sirius, Somno Comfort2 and the VENTIclick generated this amount of humidity only at low flow rates of 20 l/min. The three humidifiers mentioned last generated a relative humidity of only 68 - 76 at high flow rates of 90 l/min. The Respiflo generates a humidity of about 90% at each flow rate (1 - 5 l/min.), independent of being filled with NaCl 0.9% or Aqua dest. CONCLUSION: Factors determinating the efficacy of humidifiers are the velocity of the airstream, the temperature of the water, the contact surface of the air and water compartments and the turbulence of the airstream. In vivo the amount of leakage is a very important determinant for the velocity of the airstream. In the care of mechanically ventilated patients one should have an approximate idea of the magnitude of the applied air flows. The limitations of some humidifiers should be known. The simple presence of a humidifier in combination with a respirator does not mean that the problem of dryness of the airway mucosa is eliminated.

[Follow-up examination and probatory CPAP therapy of obstructive sleep apnoea increase the long-term compliance]. / Poststationäre Nachsorge und probatorische CPAP-Therapie schlafbezogener obstruktiver Atemstörungen steigern die Langzeitcompliance.

INTRODUCTION: Since the implementation of CPAP therapy in the treatment of obstructive sleep apnoea in the 1980 s researchers have been looking for predictors and possibilities to improve long-term compliance. In a prospective randomised trial we examined the influence of a follow-up examination two weeks after the start of probatory CPAP therapy compared to immediate prescription of the CPAP device. METHODS: 249 new patients with a newly diagnosed obstructive sleep apnoea (OSA) started with a CPAP therapy. These patients were prospectively randomised depending on the dates of admission (even/uneven). The CPAP device for the first group was immediately prescribed. Patients of the second group were seen in our sleep laboratory ambulance after a probatory usage of the CPAP therapy over a period of fourteen days. After 433 +/- 138 days we measured the compliance by reading off the operating hours counter. In order to collect these data all patients received written simple instructions how to read off the operating hours counter. They sent back the results via a prepaid return envelope. In addition, we obtained the information as to whether a hot water bath humidifier was used. RESULTS: 171 of the initially 249 patients sent back the evaluation form. The randomisation of the groups was successful concerning: age, sex as well as the apnoea-hypopnoea index before and under CPAP therapy. 226 patients were treated with the fix-CPAP mode (mean pressure 8.1 +/- 1.8 cm H(2)O), 23 patients received auto CPAP therapy. The patients with a probatory CPAP therapy and follow-up examination showed a significantly (p = 0.01) better compliance of nocturnal CPAP use with 4.5 +/- 1.8 h/night versus those who had their CPAP device immediately prescribed with a use of 3.8 +/- 2.1 h/night. The percentage of patients with a use of CPAP more than 4 h/night was significantly higher in the group with probatory therapy (66.3 % vs. 45.6 %; p = 0.008). Patients with probatory CPAP therapy made more use of humidifiers than the immediate prescription group; however, the use of a humidifier did not have any significant influence on the long-term compliance (p = 0.58). CONCLUSION: The combination of probatory CPAP therapy and follow-up examination increases the long-term compliance significantly in the treatment of obstructive sleep apnoea.

[Expiratory pressure reduction (C-Flex Method) versus fix CPAP in the therapy for obstructive sleep apnoea]. / Exspiratorische Druckabsenkung (C-Flex) versus konstantem CPAP in der Therapie schlafbezogener obstruktiver Atemstörungen.

INTRODUCTION: The REM star C-Flex (Fa. Respironics) was introduced in 2003. In contrast to the conventionel fix CPAP mode, the C-Flex mode is characterised by a pressure reduction at the beginning of expiration. In a randomised cross-over design, we investigated if this C-Flex-mode has advantages compared to the fix CPAP mode in terms of treatment quality and patient satisfaction. METHODS: In this prospective randomised single-blinded cross-over study we investigated 20 patients with obstructive sleep apnoea treated with fix CPAP versus treatment with the C-Flex mode (level 2) for 6 weeks, respectively. We compared the polysomnographically measured quality of treatment and the subjective satisfaction of either form of therapy. Additionally, we measured long-term compliance of the C-Flex therapy in a 3-year follow-up with the integrated counter of the C-Flex devices. RESULTS: The mean levels of pressure of the fix CPAP and the C-Flex therapies were 8.4 +/- 2.9 mbar in both groups. There was an identical quality of treatment in terms of respiratory events, arousal index, slow wave sleep and Epworth sleepiness scale. The compliance of nocturnal use of the C-Flex and the fix CPAP was identical (6.0 +/- 0.67 C-Flex use vs. 5.8 +/- 0.98 CPAP use [h/night]). The subjective satisfaction was higher in the C-Flex mode at the end of the study since 18 of 20 patients (90%) subjectively prefered the C-Flex mode because of the easier expiration. 19 patients received a C-Flex device for long-term therapy. The 3-year-follow-up showed a regular utilisation of the C-Flex by 16 of 19 (84.2%) of these patients (mean nocturnal use 6.0 +/- 0.9 h/night). 3 of the 19 patients (15.8%) did not use their C-Flex regulary. None of the patients has terminated therapy completely. CONCLUSION: C-Flex mode and the conventional fix CPAP therapies show an equivalent treatment quality according to polysomnographic data. The expiratory pressure reduction compared to conventional CPAP was felt to be more comfortable by 90% of patients. The long-term-compliance as measured by regular use of the C-Flex device was 84.2% (16 out of 19 patients) after 3 years, these numbers are higher than published data on compliance with conventional CPAP therapy.

Molecular mapping of resistance genes to tan spot [Pyrenophora tritici-repentis race 1] in synthetic wheat lines.

Synthetic wheat lines (2n = 6x = 42, AABBDD), which are amphiploids developed from the hybrid between tetraploid wheat (Triticum turgidum L., 2n = 4x = 28, AABB) and Aegilops tauschii Coss. (2n = 2x = 14, DD), are important sources of resistance against tan spot of wheat caused by Pyrenophora tritici-repentis. In the present study, inheritance, allelism and genetic linkage analysis in synthetic wheat lines have been carried out. Segregation analysis of the phenotypic and molecular data in F(2:3) populations of CS/XX41, CS/XX45, and CS/XX110 has revealed a 1:2:1 segregation ratio indicating that resistance of tan spot in these synthetic lines is controlled by a single gene. Allelism tests detected no segregation for susceptibility among F(1) and F(2) plants derived from intercrosses of the resistance lines XX41, XX45 and XX110 indicating that the genes are either allelic or tightly linked. Linkage analysis using SSR markers showed that all the three genes: tsn3a in XX41, Tsn3b in XX45 and tsn3c in XX110 are clustered in the region around Xgwm2a, located on the short arm of chromosome 3D. The linked markers and genetic relationship of these genes will greatly facilitate their use in wheat breeding and deployment of cultivars resistant to tan spot.

Relief of reflux symptoms after endoscopic gastroplication may be associated with reduced esophageal Acid sensitivity: a pilot study.

BACKGROUND AND STUDY AIMS: Although the new endoscopic techniques for the treatment of gastroesophageal reflux disease (GERD) lead to marked clinical benefit, the underlying mechanism of this is unknown. MATERIALS AND METHODS: In this prospective study, the effect of endoscopic gastroplication was investigated in six patients with GERD, who were assessed before and 4 weeks after treatment. The effect on reflux symptoms, quality of life, proton pump inhibitor (PPI) consumption, reflux esophagitis, acid exposure, esophageal motility, lower esophageal sphincter pressure (LESP), and gastric emptying was measured. Esophageal acid sensitivity before and after treatment was investigated using a standardized acid provocation test, and compared with that of six age- and sex-matched healthy controls. RESULTS: Significant clinical benefit and discontinuation of PPI consumption after gastroplication was seen. Among the objectively measured parameters, only acid exposure was significantly reduced and gastric emptying significantly delayed. However, acid exposure remained pathologically high. Esophageal acid sensitivity was significantly reduced. The induction of heartburn and/or pain was abolished in four patients after gastroplication. In two patients the intensity of heartburn/pain was significantly reduced by 40 % or 60 %, and the time to provoke heartburn/pain significantly prolonged by 40% or 100%. CONCLUSION: These preliminary data suggest that the decrease of esophageal sensitivity to acid after endoscopic gastroplication is part of the mechanism responsible for the reduction of reflux symptoms.

Comparative analysis of Phytophthora infestans induced gene expression in potato cultivars with different levels of resistance.

Differential gene expression was analyzed after infection with Phytophthora infestans in six potato cultivars with different levels of resistance to late blight. To verify the infection of the potato leaflets, the amount of phytopathogen mRNA within the plant material was quantified by real-time quantitative PCR. The expression of 182 genes selected from two subtracted cDNA libraries was studied with cDNA array hybridization using RNA from non-infected and infected potato leaflets. Gene up- and down-regulation were clearly detectable in all cultivars 72 h post inoculation. Gene expression patterns in susceptible cultivars differed from those in potato varieties with a higher level of resistance. In general, a stronger gene induction was observed in the susceptible cultivars compared to the moderately to highly resistant potato varieties. Five genes with the highest homology to stress and/or defence-related genes were induced specifically in the susceptible cultivars. Four genes responded to pathogen attack independently of the level of resistance of the cultivar used, and three genes were repressed in infected tissue of most cultivars. Even in the absence of P. infestans infection, six genes showed higher expression levels in the somewhat resistant cultivars Bettina and Matilda. Possible reasons for the different levels of gene expression are discussed.

[Unusually long latency before the appearance of Frey's syndrome after parotidectomy]. / Aussergewöhnlich lange Latenz für das Auftreten des Frey-Syndroms nach Parotidektomie.

We report on an unusual case of Frey's syndrome. A 45 year old male patient presented with gustatory sweating 14 years after parotidectomy. The sialography showed a post-parotidectomy status without any pathologic findings. The MRI also showed a normal rest-parenchyma of the parotid gland without any pathologic findings. Minor's starch iodine test [14], confirmed the gustatory sweating in the left preauricular area. Frey's syndrome can appear with a latency of 14 years postoperative or post-trauma. The pathogenic mechanism and the curative therapy for this auriculotemporal-syndrome are still unsolved.

Development and validation of a PCR-based marker assay for negative selection of the HMW glutenin allele Glu-B1-1d (Bx-6) in wheat.

Polymorphisms between the coding sequences of high-molecular-weight (HMW) glutenin x-type genes at the Glu-1 locus were used to amplify Glu-1B x-type-specific PCR fragments. PCR analysis in a wheat cultivar subset carrying different Glu-1B x-type alleles resulted in PCR fragments that differed in size for Glu-B1-1d (B-x6) and non -Glu-B1-1d (B-x6) genotypes. Subsequent sequencing analysis revealed a 15-bp in-frame insertion in the coding regions of all Glu-B1-1d (B-x6) genotypes which allowed the development of a B-x6-specific PCR assay for high-throughput allele sizing by ion-pair reversed-phase high-performance liquid chromatography. The assay was validated in a set of 86 German wheat cultivars, and genotyping data unequivocally verified the presence of HMW glutenin subunits GLU-B1-1D (Bx-6) + GLU-B1-2A (By-8) by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis. These results demonstrate that the PCR assay can be applied for the detection and negative selection of the 'poor breadmaking quality' Glu-B1-1d (B-x6) alleles in wheat breeding programs.

Localization of a novel recessive powdery mildew resistance gene from common wheat line RD30 in the terminal region of chromosome 7AL.

Segregation analysis of resistance to powdery mildew in a F(2) progeny from the cross Chinese Spring (CS) x TA2682c revealed the inheritance of a dominant and a recessive powdery mildew resistance gene. Selfing of susceptible F(2) individuals allowed the establishment of a mapping population segregating exclusively for the recessive resistance gene. The extracted resistant derivative showing full resistance to each of 11 wheat powdery mildew isolates was designated RD30. Amplified fragment length polymorphism (AFLP) analysis of bulked segregants from F(3)s showing the homozygous susceptible and resistant phenotypes revealed an AFLP marker that was associated with the recessive resistance gene in repulsion phase. Following the assignment of this AFLP marker to wheat chromosome 7A by means of CS nullitetrasomics, an inspection of simple sequence repeat (SSR) loci evenly spaced along chromosome 7A showed that the recessive resistance gene maps to the distal region of chromosome 7AL. On the basis of its close linkage to the Pm1 locus, as inferred from connecting partial genetic maps of 7AL of populations CS x TA2682c and CS x Virest ( Pm1e), and its unique disease response pattern, the recessive resistance gene in RD30 was considered to be novel and tentatively designated mlRD30.

QTL mapping for resistance against non-parasitic leaf spots in a spring barley doubled haploid population.

Phenotypic variability for resistance against non-parasitic leaf spots (NPLS) has been observed between varieties. For the genetic characterization of NPLS resistance, a population with 430 doubled haploid (DH) lines was developed from the cross between the NPLS-resistant Hordeum vulgare breeding line IPZ24727 and the NPLS-sensitive barley cultivar Barke. A molecular map was constructed based on 164 AFLPs, 30 SSRs and one STS marker derived from the mlo gene. Field trials were performed over four environments in which NPLS and other agronomic traits were assessed. Estimates of genotypic variance were highly significant for NPLS. Moreover, no transgression was found for the trait. Quantitative trait loci (QTLs) for NPLS resistance were mapped in the DH population on chromosomes 1H, 4H, and 7H, with the most important effect on chromosome 4H. The QTLs for NPLS explained together 39% of the phenotypic and 49% of the genotypic variance, thereby showing additive gene action. Consequently, marker-assisted selection for improving NPLS resistance is possible.

Production of haploids from anther culture of banana [Musa balbisiana (BB)].

We report here, for the first time, the production of haploid plants of banana Musa balbisiana (BB). Callus was induced from anthers in which the majority of the microspores were at the uninucleate stage. The frequency of callus induction was 77%. Callus proliferation usually preceded embryo formation. About 8% of the anthers developed androgenic embryos. Of the 147 plantlets obtained, 41 were haploids (n=x=11). The frequency of haploid production depended on genotypes used: 18 haploid plants were produced from genotype Pisang klutuk, 12 from Pisang batu, seven from Pisang klutuk wulung and four from Tani. The frequency of regeneration was 1.1%, which was based on the total number of anthers cultured. Diploid plants (2n=2x=22) were also observed in the regenerated plants. The haploid banana plants that were developed will be important material for the improvement of banana through breeding programmes.

[Universal newborn hearing screening program in Würzburg. Experience with more than 4000 newborns and the influence of non-pathological factors on the test results]. / Das Würzburger Hörscreening-Programm bei Neugeborenen. Erfahrungen bei mehr als 4000 Säuglingen - Einfluss nichtpathologischer Faktoren auf die Messergebnisse.

BACKGROUND: The BERAphon(R) method employing a special headphone and the time-course step-stimulus algorithm offers a quick and reliable tool for universal hearing screening in newborns. An ABR-based universal newborn hearing screening program has been established in Würzburg since August, 1997. Until August 2001, 4115 newborns have undergone primary and/or control-screening with the BERAphon(R). The validity of this method was further examined by testing the effects of non-pathological factors such as gender, age, Apgar score, pH value of the umbilical cord, head circumference and duration of pregnancy on the ABR wave V latency in 415 infants. RESULTS: Out of 3930 infants who were primary screened, 27 infants were diagnosed to have hearing loss. Furthermore, hearing loss was detected in 35 out of 185 infants referred for control screening. Non-pathological factors showed a minor effect on the test results. Apgar score, gender or chronological age did not have any significant effects on the latency of wave V. Duration of pregnancy, pH value of the umbilical cord or head circumference showed a significant but weak correlation with wave V latency. CONCLUSIONS: Only non-pathological factors related to maturation had a minor effect on ABR measurements using the time-course-step-stimulus algorithm. The BERAphon(R) method has proven to be a reliable, robust method giving information related to the hearing threshold and accordingly can be used reliably for hearing screening in newborn infants.

A resistance gene analog useful for targeting disease resistance genes against different pathogens on group 1S chromosomes of barley, wheat and rye.

Comparative sequence analysis of the resistance gene analog (RGA) marker locus aACT/CAA (originally found to be tightly linked to the multiallelic barley Mla cluster) from genomes of barley, wheat and rye revealed a high level of relatedness among one another and showed high similarity to a various number of NBS-LRR disease resistance proteins. Using the sequence-specific polymerase chain reaction (PCR), RGA marker aACT/CAA was mapped on group 1S chromosomes of the Triticeae and was associated with disease resistance loci. In barley and rye, the marker showed linkage to orthologous powdery mildew resistance genes Mla1 and Pm17, respectively, while in wheat linkage with a QTL against fusarium head blight (FHB) disease was determined. The use of RGA clones for R gene mapping and their role in the expression of qualitative and quantitative resistance is discussed.