Inkjet-printed stretchable and low voltage synaptic transistor array.

Wearable and skin electronics benefit from mechanically soft and stretchable materials to conform to curved and dynamic surfaces, thereby enabling seamless integration with the human body. However, such materials are challenging to process using traditional microelectronics techniques. Here, stretchable transistor arrays are patterned exclusively from solution by inkjet printing of polymers and carbon nanotubes. The additive, non-contact and maskless nature of inkjet printing provides a simple, inexpensive and scalable route for stacking and patterning these chemically-sensitive materials over large areas. The transistors, which are stable at ambient conditions, display mobilities as high as 30 cm2 V-1 s-1 and currents per channel width of 0.2 mA cm-1 at operation voltages as low as 1 V, owing to the ionic character of their printed gate dielectric. Furthermore, these transistors with double-layer capacitive dielectric can mimic the synaptic behavior of neurons, making them interesting for conformal brain-machine interfaces and other wearable bioelectronics.

[Fatal course of infectious mononucleosis in an 11-month-old girl]. / Tödliche Verlaufsform einer infektiösen Mononukleose bei einem 11 Monate alten Mädchen.

Fatal infectious mononucleosis is vary rare in the human population. Only two case reports of girls suffering an Epstein-Barr virus-associated lymphoproliferation without evidence of an underlying immunodeficiency came to our knowledge. We report on the case of an 11-months-old girl with fatal infectious mononucleosis. Some findings allow distinct delineation from previous reports. Firstly, the present "pulmonary lymphoid hyperplasia" has been formerly described in patients with HIV infection exclusively. Secondly, only the EBV surface antigen LMP was expressed on infected B-cells. The nuclear antigen complex EBNA could not be demonstrated. Overall, the results suggest a so far unrecognised type of EBV-associated lymphoproliferation in a female infant.

Reactivity of young and old human enamel to demineralization.

The aim of this study was to determine the susceptibility of newly erupted and old permanent teeth to artificial, caries-like attacks. Two groups of caries-free teeth were used. Group 1 consisted of 38 teeth extracted for orthodontic reasons (9-12-yr-old children); group 2, of 40 teeth extracted for periodontal reasons (45-65-yr-old patients). After thorough cleaning, a test window was isolated on the incisal two-thirds of the buccal surface. After demineralization with 6% HEC gel at pH 4.9 for 8 days, longitudinal ground sections were prepared for imbibition studies in polarized light and for secondary ion mass spectrometry (SIMS). In the young teeth, the lesions appeared to be uniform in their extension in the enamel, whereas the old teeth showed less marked and thinner surface zones and greater depth of the positively birefringent body of the lesion. Polarized light microscopy and SIMS data support the hypothesis that there are different enamel pathways in the initiation of the natural carious process.

Non-isotopic analysis of single strand conformation polymorphism (SSCP) in the exon 13 region of the human dystrophin gene.

More than 30% of Duchenne and Becker muscular dystrophy (DMD/BMD) patients have no gross DNA rearrangements like deletions or duplications. The large size of the coding sequence of the dystrophin gene (11 kilobases) complicates systematic identification of point mutations. Recently reported approaches based on genomic DNA or mRNA show that chemical cleavage of mismatches is an effective but time consuming and technically demanding method for the identification of point mutations in the human dystrophin gene. We have used a fast and convenient system consisting of PCR amplification of genomic DNA, non-isotopic SSCP analysis, and direct sequencing of PCR products for the detection of mutations in exon 13 and adjacent intron sequences. Sixty-eight DMD patients without detectable deletions or duplications were analysed, resulting in the identification of a point mutation in the coding sequence and two polymorphisms in the 5' flanking intron. The C to T change of the first nucleotide in the third triplet leads to a stop codon and seems to be the cause of the functional deficiency of the gene product in this patient.

Alternative splicing of dystrophin mRNA complicates carrier determination: report of a DMD family.

Carrier determination is important for genetic counselling in DMD/BMD families. The detection of altered PCR amplified dystrophin mRNA fragments owing to deletions, insertions, or point mutations has increased the possibilities of carrier determination. However, problems may occur because of alternative splicing events. Here we present a family with a DMD patient characterised by a deletion of exons 45 to 54. At the mRNA level we detected a corresponding altered fragment which served for carrier determination. The mother and the sister of the patient showed the same altered dystrophin mRNA fragment as the patient and are therefore carriers. In the mother two additional altered dystrophin mRNA fragments were detectable, obviously resulting from alternative splicing in the normal allele. The grandmother and two other related females of the patient possess only the normal mRNA fragment. In a further female we detected an altered fragment owing to an mRNA deletion of exon 44. This fragment is created either by alternative splicing or a new mutation. Therefore, the carrier status of this female is still ambiguous indicating problems in carrier determination by the method of dystrophin mRNA analysis.

Deletion analysis of DMD/BMD families from the German Democratic Republic and selected regions of Czechoslovakia and Hungary.

Over the last two years we have screened 183 DMD/BMD families requesting prenatal diagnosis. Using cDNA probes cf56a,b we have detected exon deletions in 72 of them. In 62 cases the deletion was also detectable with currently available PCR primers. Deletion analysis for exons 8, 17, and 19, using either PCR or Southern blotting techniques, was performed for 65 of the 111 families which showed no deletions with cf56a,b. Eight of them were deleted for one or more of these exons. PCR offers new possibilities for deletion analysis in families without a living patient using either Guthrie papers or histologically conserved material from the dead patient. In 20 of 25 patients, we observed concordance between the clinical picture and the molecular deletion analysis in accordance with the open reading frame hypothesis. Five patients, however, presented with DMD in spite of our analysis showing an in frame deletion. Carrier determination in families in which DMD is caused by a deletion using linkage, dosage, or breakpoint analysis is discussed.

[Biocompatibility of various surgical drainage materials in the cytotoxicity and implantation test]. / Untersuchungen zur Biokompatibilität verschiedener chirurgischer Drainagematerialien im Zytotoxizitäts- und Implantationstest.

The biocompatibility of 10 materials used for surgical drainage was evaluated in a cytotoxicity test and in rat subcutaneous tissue implantation test. All rubber materials and silikolatex were found to be cytotoxic. There was no correspondence of the results of the cytotoxicity test with those of the implantation test. Therefore various procedures for biocompatibility-testing should be used.

The effect of lincomycin-neomycin treatment on experimental anaerobic bacterial bovine mastitis.

Three healthy lactating quarters of a Friesland cow were each experimentally infected with a pure culture of a strain of either Bacteroides fragilis, Eubacterium lentum or a Peptostreptococcus sp. respectively. The onset and progression to clinical mastitis was monitored 12 hourly by examination for clinical signs of inflammation, bacterial culture, somatic cell counts and with a strip cup. All infected quarters developed clinical mastitis within 24 hours. The 2 quarters infected with B. fragilis and E. lentum respectively were treated 4 times consecutively at 12 hour intervals, commencing at 24 h by intramammary instillation of 10 ml of a mixture containing 200 mg lincomycin hydrochloride, 200 mg neomycin sulphate and 5 mg methylprednisolone (Lincocin Forte, Upjohn). Both quarters became clinically normal and no bacteria could be detected in the secretions 12 hours after the first treatment. At 36 hours the strip cup became negative, and the somatic cell count dropped to less than 500 X 10(3) at 72 hours after the initial treatment. The quarter infected with a Peptostreptococcus sp. was unable to overcome the infection by natural means when intramammary treatment was delayed for the first 36 hours after the onset of clinical mastitis. Subsequent treatment of this quarter gave results similar to those treated earlier.

[Effect of dopaminergic substances on the antinocifensive action of arecoline]. / Beeinflussbarkeit der antinozifensiven Wirkung von Arekolin durch dopaminerge Substanzen.

Based on earlier studies that revealed the analogical influence of noradrenaline and serotonin on morphine analgesia and the antinocifensive effect of arecoline, it was tested whether under the influence of dopaminergic substances the inhibition of nocifensive reactions is being altered by arecoline like the action of morphine. In fact, arecoline could be amplified in a dose dependent manner by apomorphine and amphetamine, which alone had no antinocifensive effects. On the other hand, no antagnoism of the dopamine receptor blockers, chloropromazine ahd haloperidole, against arecoline was demonstrable; only the additive effect of apomorphine and amphetamine could be abolished. Therefore it is concluded that dopamine is not directly involved in the spinal mechanism of the antinocifensive effect of central cholinomimetics, but that only supraspinal influences can be varied by the function of dopaminergic neurons.