Mold spectrum of four cereal brands of the German crop 1995

The concentration of extracellular polysaccharides (EPS) of 80 cereal grain samples of the German harvest 1995 was investigated. In addition to this, the total as well as the inherent mycoflora of two winter wheat and two winter rye brands which showed the highest EPS-concentration was detected on maltsalt agar (NaCl 5%). Surface disinfection with 1% NaOCl for the determination of the internal mycoflora caused a significant reduction in number and kind of fungi. However, the mycoflora of all samples was dominated by fungi of the genera Alternaria spp. and Cladosporium spp., Aureobasidium pullulans, Fusarium spp. and Epicoccum purpurascens (in decreasing order) occurred to a minor extent. A possible contamination of the cereal grains with mycotoxins of Alternaria and Cladosporium is discussed.

Maternal smoking during pregnancy and lactation increases the risk for atopic eczema in the offspring

BACKGROUND

Maternal smoking during pregnancy has been shown to lead to immunologic changes in the offspring. However, little is known about the influence of this exposure on atopic manifestations.

OBJECTIVE

Our purpose was to investigate the influence of air pollutants on manifestations of atopy in preschool children.

METHODS

Unselected cohorts of a total of 678 5- to 6-year-old preschool children (350 boys, 328 girls) were investigated in areas with different degrees of air pollution in Bavaria. Data on the history of atopic diseases and other relevant factors were obtained by questionnaire. A skin-prick test was performed with common aeroallergens. Manifestation of atopy was defined as personal history of atopic disease or positive prick test to either grass pollen, house dust mite, or cat and analyzed multivariately.

RESULTS

Of all children, 38.9% exhibited at least one manifestation of atopy. Atopic eczema was reported in 7.9% to 15.5%, hayfever in 4.1% to 25.6%, and asthma in 3.0% to 8.1%. Of the mothers, 12.6% smoked during pregnancy or lactation or both. Analysis of the manifestation of atopy including sex, location, nitrogen oxide and sulfur dioxide exposure and maternal smoking as covariates revealed an influence of the maternal smoking during pregnancy/lactation. Of children whose mothers had smoked during pregnancy/lactation, 52.2% exhibited manifestations of atopy in contrast to 35.7% of children of nonsmoking mothers (p < 0.044). A history of atopic eczema was the only component of the variable "manifestation of atopy" that was significantly associated with maternal smoking during pregnancy and lactation. A causal interpretation of this finding, however, was not supported by a follow-up study.

CONCLUSION

Maternal smoking during pregnancy or lactation or both might play a role in the development of atopic eczema and should be avoided.

The neuronal cell-adhesion molecule axonin-1 is specifically released by an endogenous glycosylphosphatidylinositol-specific phospholipase

Axonin-1, a member of the immunoglobulin/fibronectin type-III family of cell-adhesion molecules, occurs both as a glycosylphosphatidylinositol-(glycosylPtdIns)-anchored membrane-bound and a soluble form. In vivo observations show that the major part of axonin-1 is found in the soluble fraction and that soluble axonin-1 perturbs neurite fasciculation and pathfinding in the developing chicken embryo. This has prompted further investigations into the mechanism of the axonin-1 release. We demonstrate here that axonin-1 released from dorsal root ganglion neurons contains ethanolamine and inositol, components of the glycosylPtdIns anchor. Secreted axonin-1 does not exhibit the cross-reacting determinant epitope, an indication that the cleavage of the anchor is not mediated by a phosphatidylinositol-specific phospholipase C. Treatment of dorsal root ganglion neurons with 1,10-phenanthroline, an inhibitor of glycosylPtdIns-specific phospholipase D, reduces the release of axonin-1 by 56%. Moreover, glycosylPtdIns-specific phospholipase D activity was detected in dorsal root ganglion neurons and brain. These results suggest that axonin-1 is released from the membrane by an endogenously expressed glycosylPtdIns-specific phospholipase D in vivo. With domain-swaping experiments between axonin-1 and its non-released relative F11, deletion mutants and monoclonal antibodies, we demonstrate that the fourth fibronectin type-III-like domain of axonin-1 is required for the generation of the soluble form of axonin-1.

Adenovirus-mediated gene transfer in neurons: construction and characterization of a vector for heterologous expression of the axonal cell adhesion molecule axonin-1

By homologous recombination, a first-generation adenovirus-based gene transfer vector, AdCMVax-1, was constructed as a means of manipulating the expression level of the axonal cell adhesion molecule axonin-1 in neurons and glial cells. AdCMVax-1 harbours the entire coding region of the chicken axonin-1 cDNA under the transcriptional control of the Cytomegalovirus enhancer/promoter in the early-region 1 of the viral genome. Characterization of AdCMVax-1 in vitro revealed highly efficient gene transfer and expression of recombinant axonin-1 in neurons and glial cells of dissociated rat dorsal root ganglia. Similar to its native counterpart, virus-derived axonin-1 was detected on the cell body, neurites, and growth cones of transduced neurons, occurred in a secreted and membrane-associated form, and could be cleaved from the membrane with phosphatidylinositol-specific phospholipase C. Functional characterization of recombinant axonin-1 revealed the same binding properties as previously reported for native axonin-1 isolated from the vitreous fluid of chicken embryos. In vivo gene transfer was studied by stereotactic injection of AdCMVax-1 in the dentate gyrus of the hippocampus and the facial nucleus in the brainstem of adult Wistar rats and revealed high level expression of recombinant axonin-1 in a subset of hippocampal neurons and motor neurons in the facial nucleus.

Clinical validation and guidelines for the SCORAD index: consensus report of the European Task Force on Atopic Dermatitis

BACKGROUND

We have previously reported how the SCORAD index was designed. This cumulative index combines objective (extent and intensity of lesions) and subjective (daytime pruritus and sleep loss) criteria.

AIMS

To study interobserver variability in scoring for objective SCORAD criteria and to optimize the scoring guidelines.

MATERIAL AND METHODS

Three scoring sessions were organized in 1993-1994 in Hamburg, Bordeaux and Rotterdam totalizing 19 patients (14 children and 5 adults) and 23 physicians, among whom 12 participated in at least 2 scoring sessions; 169 evaluation sheets have been processed using the SCORAD File Marker Pro software. At each session, total body photographs and close-up views were taken of each patient, and this material was reviewed at the final evaluation.

RESULTS

The extent of lesions according to the rule of nines showed interobserver variability mostly for patients with lesions of moderate intensity involving 20-60% of body surface. Intensity items were scored with more consistency overall, but variations subsided especially for oozing/crusts and lichenifications. Low and high scorer profiles and the benefit of training were noted.

CONCLUSIONS

This study has allowed to optimize clinical scoring using the SCORAD system. A proposal has been made to grade the severity of atopic dermatitis according to objective criteria in three groups for inclusion in clinical trials. The SCORAD index remains the major criterion for follow-up in trials.

Cell adhesion molecules NgCAM and axonin-1 form heterodimers in the neuronal membrane and cooperate in neurite outgrowth promotion

The axonal surface glycoproteins neuronglia cell adhesion molecule (NgCAM) and axonin-1 promote cell-cell adhesion, neurite outgrowth and fasciculation, and are involved in growth cone guidance. A direct binding between NgCAM and axonin-1 has been demonstrated using isolated molecules conjugated to the surface of fluorescent microspheres. By expressing NgCAM and axonin-1 in myeloma cells and performing cell aggregation assays, we found that NgCAM and axonin-1 cannot bind when present on the surface of different cells. In contrast, the cocapping of axonin-1 upon antibody-induced capping of NgCAM on the surface of CV-1 cells coexpressing NgCAM and axonin-1 and the selective chemical cross-linking of the two molecules in low density cultures of dorsal root ganglia neurons indicated a specific and direct binding of axonin-1 and Ng-CAM in the plane of the same membrane. Suppression of the axonin-1 translation by antisense oligonucleotides prevented neurite outgrowth in dissociated dorsal root ganglia neurons cultured on an NgCAM substratum, indicating that neurite outgrowth on NgCAM substratum requires axonin-1. Based on these and previous results, which implicated NgCAM as the neuronal receptor involved in neurite outgrowth on NgCAM substratum, we concluded that neurite outgrowth on an NgCAM substratum depends on two essential interactions of growth cone NgCAM: a trans-interaction with substratum NgCAM and a cis-interaction with axonin-1 residing in the same growth cone membrane.

Cloning of a cDNA encoding a plasma membrane-associated, uronide binding phosphoprotein with physical properties similar to viral movement proteins

Oligogalacturonides are structural and regulatory homopolymers from the extracellular pectic matrix of plants. In vitro micromolar concentrations of oligogalacturonates and polygalacturonates were shown previously to stimulate the phosphorylation of a small plasma membrane-associated protein in potato. Immunologically cross-reactive proteins were detected in plasma membrane-enriched fractions from all angiosperm subclasses in the Cronquist system. Polygalacturonate-enhanced phosphorylation of the protein was observed in four of the six dicotyledon subclasses but not in any of the five monocotyledon subclasses. A cDNA for the protein was cloned from potato. The deduced protein is extremely hydrophilic and has a proline-rich N terminus. The C-terminal half of the protein was predicted to be a coiled coil, suggesting that the protein interacts with other macromolecules. The recombinant protein was found to bind both simple and complex galacturonides. The behavior of the protein suggests several parallels with viral proteins involved in intercellular communication.

Intracellular signaling is changed after clustering of the neural cell adhesion molecules axonin-1 and NgCAM during neurite fasciculation

Neural cell adhesion molecules of the immunoglobulin/fibronectin type III family on axons have been implicated in promotion of neurite outgrowth, fasciculation, and the mediation of specific cell adhesion. The present study demonstrates that two of these molecules on dorsal root ganglion neurons are associated with distinct protein kinases, axonin-1 with the src-related nonreceptor tyrosine kinase fyn and NgCAM with a casein kinase II-related activity and a serine/ threonine kinase related to S6 kinase. When neurites grew without contacts involving axonin-1 and NgCAM, strong fyn kinase activity was associated with axonin-1, whereas the NgCAM-associated kinase activities were low. Clustering of axonin-1 with NgCAM induced by the formation of cell-cell contacts correlated with a reduction of the axonin-1-associated fyn activity and an increased phosphorylation of NgCAM by the associated casein kinase II-related activity. Thus, axonin-1 and NgCAM trigger distinctive intracellular signals during in vitro differentiation depending on their state of association.

Continuous renewal of the axonal pathway sensor apparatus by insertion of new sensor molecules into the growth cone membrane

BACKGROUND

Growth cones at the tips of growing axons move along predetermined pathways to establish synaptic connections between neurons and their distant targets. To establish their orientation, growth cones continuously sample for, and respond to, guidance information provided by cell surfaces and the extracellular matrix. To identify specific guidance cues, growth cones have sensor molecules on their surface, which are expressed differentially during the temporospatial progress of axon outgrowth, at levels that depend on the pattern of neural activity. However, it has not been elucidated whether a change in gene expression can indeed change the molecular composition and, hence, the function of the sensor apparatus of growth cones.

RESULTS

We have constructed adenoviral gene transfer vectors of the chicken growth cone sensor molecules axonin-1 and Ng-CAM. Using these vectors, we initiated the expression of axonin-1 and Ng-CAM in rat dorsal root ganglia explants during ongoing neurite outgrowth. Using specific surface immunodetection at varying time points after infection, we found that axonin-1 and Ng-CAM are transported directly to the growth cone and inserted exclusively in the growth cone membrane and not in the axolemma of the axon shaft. Furthermore, we found that axonin-1 and Ng-CAM do not diffuse retrogradely, suggesting that the sensor molecules are integrated into multimolecular complexes in the growth cone.

CONCLUSIONS

During axon outgrowth, the pathway sensor apparatus of the growth cone is continuously updated by newly synthesized sensor molecules that originate directly from the transcription/translation machinery. Changes in the expression of sensor molecules may have a direct impact, therefore, on the exploratory function of the growth cone.

Implications for the domain arrangement of axonin-1 derived from the mapping of its NgCAM binding site

The neuronal cell adhesion molecule axonin-1 is composed of six immunoglobulin and four fibronectin type III domains. Axonin-1 promotes neurite outgrowth, when presented as a substratum for neurons in vitro, via a neuronal receptor that has been identified as the neuron-glia cell adhesion molecule, NgCAM, based on the blocking effect of polyclonal antibodies directed to NgCAM. Here we report the identification of axonin-1 domains involved in NgCAM binding. NgCAM-conjugated microspheres were tested for binding to COS cells expressing domain deletion mutants of axonin-1. In addition, monoclonal antibodies directed to axonin-1 were assessed for their ability to block the axonin-1-NgCAM interaction, and their epitopes were mapped using the domain deletion mutants. The results suggest that the four amino-terminal immunoglobulin domains of axonin-1 form a domain conglomerate which is necessary and sufficient for NgCAM binding. Surprisingly, NgCAM binding to membrane-bound axonin-1 was increased strongly by deletion of the fifth or sixth immunoglobulin domains of axonin-1. Based on these results and on negative staining electron microscopy, we propose a horseshoe-shaped domain arrangement of axonin-1 that obscures the NgCAM binding site. Neurite outgrowth studies with truncated forms of axonin-1 show that axonin-1 is a neurite outgrowth-promoting substratum in the absence of the NgCAM binding site.

[Study on the pretherapeutic differential diagnosis of adnexal tumors]

How well do clinical examination, laboratory testing and imaging techniques predict the malignant or benign characteristics of an adnexal tumor before surgery? 60 patients underwent an extensive preoperative work-up including serum levels of gonadotropins, adrenal and ovarian steroids, oncofetal and placental antigens and CA 125. Sensitivity and specificity of laboratory criteria, including CA 125, compared unfavorably with others and are of no use in early diagnosis of ovarian malignancies. The differential diagnosis of adnexal tumors is primarily a matter of PV examination and ultrasound.

[Hygienic processing of dental transmission instruments (handpieces and instruments, turbines) in dental practice]

The efficacy of a steam disinfection method for the processing of used instruments in dental practice was tested with 274 high-speed turbines and handpieces. The instruments treated with streaming steam were both taken out of the dental practice of treatment and artificially contaminated with five different test-microorganisms (E. coli, P. aeruginosa, S. aureus, E. faecium, C. albicans) and different concentrations of serum (1%, 10%, 20%). In spite of the narrow channels of these instruments a microbial reduction of more than 5 log10 steps could be achieved in all cases. Thus dental high-speed turbines and handpieces can reliably be disinfected with streaming steam.

Mycoflora of Cereal Flakes

Twelve brands of cereal flakes were examined for their qualitative and quantitative mold contamination. Higher fungal counts were observed in the case of two wheat and one oat flake sample (s) while the remaining brands showed minor contamination rates. The fungal flora consisted of 64 different species belonging to 23 fungal genera. Fungi of the genus Eurotium (4 species), Aspergillus (7 spp.) and Penicillium (25 spp.) predominated on most samples.

Mold Spectra of Various Foods in Relation to Plating Medium

Freeze-dried strawberries and pears, raisins, sliced roasted almonds, and hazelnuts were investigated for their qualitative and quantitative mycoflora on four different media. The foodstuffs investigated showed relatively low infestation rates. Slightly higher fungus counts were observed in the case of almonds, while strawberries, hazelnuts, raisins, and pears (in decreasing order) were contaminated only to a minor degree. The mycoflora was dominated by molds of the genera Aspergillus and Penicillium and fungi of the Mucoraceae. Most fungus isolates could be enumerated from DRBC, followed by PDA and DG-18, while 7.5% MSA showed only low effectiveness. Minor differences were seen when the number of different species/genera from each medium were compared with each other. DRBC allows the isolation of the broadest spectrum of fungi. Differences between the remaining media were small.

[Microbial purine decomposition]

27 microorganisms were tested for their ability to degrade extracellular purines as sole sources of carbon, nitrogen, and energy. Beside adenine, guanine, xanthine, hypoxanthine, and urate as free purine bases, this test included 5'-AMP, 5'-GMP, 5'-XMP, and 5'-IMP, as well as DNA and RNA as purine compounds. Generally, only a limited number of microbial species was capable of metabolizing the substances named above. Compared to the other species, Paracoccus denitrificans showed the greatest substrate spectrum, including the free bases as well as the mononucleotides. However, the polymers DNA and RNA were not degraded.

[Demonstration of nosocomial pathogens in the nasal swabs of medical students]

A single examination of nasal swabs of 183 medical students revealed 87 persons (47.5%) being carrier of nosocomial pathogens. Enterobacteriaceae could be isolated in 35 cases (19.1%), Staphylococcus aureus in 62 cases (33.9%). Two different species of nosocomial pathogens were found simultaneously in 10 persons, most frequently comprising Staphylococcus aureus and Enterobacteriaceae. After the first isolation of Enterobacteriaceae control studies of 20 persons done after a 3-week-period could state the primary isolation in 11 cases (55%). The findings indicate the importance of the nose as a reservoir for nosocomial--even gram-negative--pathogens.

Reactivation of transcription from a vaccinia virus early promoter late in infection

We have studied the kinetics of RNA synthesis from the vaccinia virus 7,500-molecular-weight gene (7.5K gene) which is regulated by early and late promoters arranged in tandem. Unexpectedly, after a first burst of RNA synthesis early in infection, transcription was reactivated late in infection. Reactivation was not dependent on the location of the promoter in the genome or on the presence of the upstream late regulatory sequences. The mRNA synthesized from the reactivated promoter in the late phase had the same 5' and 3' ends as the molecules transcribed in the early phase. Interestingly, these molecules were efficiently translated despite the absence of the poly(A) leader characteristic of late mRNAs. Reactivation appears to be dependent on virus assembly since it is prevented by rifampin, a specific inhibitor of morphogenesis. Finally, analysis of various other early genes showed that reactivation is not unique to the 7.5K early promoter.

Cell-cell adhesion by homophilic interaction of the neuronal recognition molecule axonin-1

The axonal surface glycoprotein axonin-1, which occurs both as a glycosyl-phosphatidylinositol-anchored membrane-bound form and a secreted form, promotes neurite outgrowth and is thought to be involved in axon-guidance mechanisms in the developing nervous system. Recently, we have demonstrated that the neurite-outgrowth-promoting activity of axonin-1, presented as a substratum for cultured neurons, is mediated by a heterophilic interaction with the axonal glycoprotein neuronglia cell-adhesion molecule (Ng-CAM). Here we present evidence for homophilic (like-like) binding among axonin-1 molecules. Axonin-1 was heterologously expressed in myeloma cells. Clonal cell lines, with exposed membrane-bound axonin-1 at their surface, formed large multicellular aggregates. Incubations of transfected and parental myeloma cells, under a series of different conditions, revealed homophilic axonin-1/axonin-1 interactions across the intermembrane space as the molecular mechanism promoting stable cell-cell contacts. Using structural and functional characterisation, recombinant axonin-1 was very similar to native axonin-1, suggesting that homophilic axonin-1 interactions are also established in neurons. The capability of axonin-1 to interact with both Ng-CAM and other axonin-1 molecules might contribute to the formation of macromolecular networks at contact sites of growth cones and axons, comprising molecules of both membranes, and thus represent a mechanism for regulating neurite outgrowth and pathfinding.

Heavy metals as selective inhibitors of mould growth

Ten heavy metals were tested in malt extract agar for their selective activity on nine food relevant fungi. The variations observed as growth inhibitory for heavy metals investigated indicated good possibility for designing selective media.

Manifestation of atopy is not related to patient's month of birth

The first months of life may be an important period for allergic sensitization. Several studies suggest a relationship between the month of birth (MB) and the development of skin sensitivity to aeroallergens or the manifestation of an atopic disease. In 1988 and 1989 we investigated a population of 1066 Bavarian preschool children aged 5-6 years. Skin prick tests were performed with common aeroallergens (grass pollen, birch pollen, house-dust mite, cat epithelia). The personal history of atopic disease (atopic eczema, allergic rhinitis, bronchial asthma) was recorded by a questionnaire, and the presence of overt atopic disease was documented by a personal examination. Positive prick test reactions to the above-mentioned aeroallergens were found in 15.4%, 9.2%, 12.2%, and 10.4% of the subjects, respectively; lifetime prevalence of manifest atopic disease was 22.2% for atopic eczema, 11.7% for allergic rhinitis, and 4.5% for asthma. The MB distributions of children reacting to aeroallergens or of those with atopic diseases were compared with those of subjects with corresponding negative findings. Chi-square tests were performed for each aeroallergen and each of the atopic diseases separately. No significant differences among the MB distributions were found (P > 0.3). Thus, in this coherent group, MB correlated neither to allergic sensitization nor to manifest atopic disease.