[The German Network for Systemic Scleroderma]. / Deutsches Netzwerk für systemische Sklerodermie.

Systemic scleroderma (SSc) is a rare, heterogenous, multisystem disease affecting different organ systems and therefore requires interdisciplinary management and patient care. The German Network for Systemic Scleroderma, funded by the country's Federal Ministry of Education and Research, was established 3 years ago and comprises dermatologists, rheumatologists, pulmonologists, and nephrologists from more than 40 medical centers. The registry contains data of more than 1800 patients. Analysis of the continually growing body of data will form the basis for the development of standardized recommendations for diagnosis and treatment of SSc.

Sexual motivation in relation to social rank in pair-housed sows.

The influence of social subordination on sexual motivation during oestrus was studied using 36 sows of which 24 treatment sows were housed in pairs and 12 control sows were housed individually in 12 and 6 m(2) pens, respectively. Video recordings were made from 07:00 h to 19:00 h during the first 2 days after grouping, which took place 3 days after weaning of the piglets. Based on the aggressive interactions between the pair-housed sows, their rank was determined. From day 4 after weaning, a test for sexual proceptive behaviour was carried out twice daily and back-pressure test was carried out four times daily in order to detect standing oestrus. When standing oestrus had occurred, transrectal ultrasonographical scans were also carried out in order to determine if ovulation took place. The proceptivity test took place in a T-maze with a 2 m x 10 m runway ending in two 1.5 m x 1.5 m goal boxes each adjacent to a stimulus compartment. One compartment contained an adult sexually experienced boar and the other was empty. Latency to and duration of time spent close to the boar and time spent presenting were recorded during the 10-min test period. On the first day that standing oestrus had been detected, a test for sexual receptivity was also carried out by introducing the sow to a mature boar in his home pen (9 m(2)). Sexual- and fear-related behaviour of sow and boar were recorded until mating was terminated or the sow had spent 5 min in the pen without mating being initiated. During oestrus the proceptivity test showed a significant increase (P < 0.05) in the time spent standing close to the boar and in presenting for single-housed sows and for pair-housed dominant sows, but not for subordinate sows. During oestrus subordinate sows spent significantly less time standing close to the boar than the dominant sows (P = 0.01) and the same tended to be the case for presenting (P = 0.07). In the receptivity test more subordinate sows than dominant sows fled (40% versus 0%, P = 0.001) and more subordinate sows than dominant sows squealed (58% versus 15%, P = 0.02) as a response to boar stimulation. In both tests, the single-housed sows differed neither from the dominant nor the subordinate sows. There was however no difference between the groups in the weaning to oestrous interval, duration of oestrus and number of piglet born. In addition, all the sows ovulated. The results indicate that social subordination can have significant consequences for sexual motivation in sows. Subordinate sows showed fear-related behaviour in response to boar stimulation even when they were in standing oestrus. Thus, both heat detection and mating may be impaired in subordinate sows. The results emphasise the importance to alleviate the social stress experienced by subordinates as well as the need for stock people to pay special attention to these animals when they are to be mated or inseminated.

Factors affecting the transfer of porcine parvovirus antibodies from sow to piglets.

The aim of the study was to investigate the effects of a number of environmental, behavioural and biological factors on passive immunization of piglets as assessed by transfer of porcine parvovirus (PPV) antibodies (ab) from the colostrum of PPV vaccinated mothers to the serum of the piglets. Twenty primiparous sows were housed in pens with peat, straw and branches for nest building. Half the sows were prevented from achieving feedback from a completed farrowing nest by repeated removal of the nest from 10 to 12 h after nest building had begun, whereas the other half kept their nests. Sow serum PPV-ab titres were positively related to colostrum PPV-ab titres at birth of the first piglet (BFP) (P < 0.001). Litter average piglet PPV-ab titre was positively related to both sow serum and colostrum PPV-ab titres (both P < 0.001). In addition, in the individual piglets. PPV-ab titres were reduced as time from BFP to birth and time from birth to first sucking increased and time spent sucking decreased (all P < 0.01). There were no effects of treatment, time spent in lateral recumbency by the sow, number of times the sow stood or piglet weight on day 1 on piglet serum PPV-ab titres. Preventing prolonged farrowing, while at the same time ensuring the piglets' access to the udder, is important for transfer of maternal immunity. Measurements of specific antibodies in sow serum during the periparturient period and in piglet serum at 28 days of age may provide a practical tool for evaluating transfer of maternal immunity from sow to piglets.

A simplified technique for non-surgical catheterization of the vena cava cranialis in pigs and an evaluation of the method.

Restraint and venepuncture affect blood parameters and are stressful for pigs. Therefore, when experiments require frequent blood sampling, catheterization is the best option, both ethically and scientifically. A simplified non-surgical method for catheterization of the vena cava cranialis in sows is described. The vena cava is catheterized via the vena jugularis externa, which is punctured while the sow is restrained by nose snaring. The procedure can be carried out by two experimenters in 5 min, it requires little equipment and can be performed under farm or very simple experimental conditions. Results from 89 catheterizations are reported. Seventy-three of the catheters remained functional for 5 days or more. There was a tendency for a higher success rate in dry sows than in highly pregnant sows. The only behavioural effect observed after catheterization was a short-lasting increase in motivation for wallowing in some sows. No illness that could be attributed to the catheterization occurred.

Inhibition of trehalase activity enhances trehalose accumulation in transgenic plants.

As a first step toward the exploitation of the disaccharide trehalose as a stress-protective and preservative agent in plants, we engineered trehalose biosynthesis in tobacco (Nicotiana tabacum) and potato (Solanum tuberosum) by introducing the otsA and otsB genes from Escherichia coli, which encode trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase, respectively. In leaves of transgenic tobacco plants, very low levels of trehalose accumulation were obtained (0.11 mg g-1 fresh weight), whereas in transgenic potato tubers, no trehalose accumulated at all. Plant trehalase activity was shown to affect the accumulation of trehalose in these plants. An increase in trehalose accumulation, up to 0.41 and 4.04 mg g-1 fresh weight in tobacco leaves and potato micro-tubers, respectively, was noted when the potent trehalase inhibitor validamycin A was added to in vitro plants and to hydroponically grown greenhouse plants. Stunted growth and the formation of lancet-shaped leaves by trehalose-accumulating tobacco plants suggest a negative effect of trehalose biosynthesis on N. tabacum development. It is surprising that experiments with wild-type plants cultured in the presence of validamycin A indicate that, despite current belief, the capacity to synthesize trehalose may not be restricted to primitive phyla of vascular plants and certain "resurrection plants," but may exist throughout the angiosperms.

Easy determination of ploidy level in Arabidopsis thaliana plants by means of pollen size measurement.

Cytogenetic examination of transgenic Arabidopsis thaliana (L.) Heynh. plants obtained by Agrobacterium-mediated gene transfer to cotyledon- and root-explants or by direct gene transfer into protoplasts revealed a high percentage of tetraploid or aneuploid transformants. Depending on the transformation procedure used, 13% (root explant transformation), 33% (cotyledon explant transformation), or 38% (direct gene transfer) of the transformants showed aberrant ploidy levels. A good correlation between the ploidy level of a plant and the size of its pollen grains was observed. This allows quick and simple testing of the ploidy level of transgenic Arabidopsis plants.

Factors influencing transformation frequency of tomato (Lycopersicon esculentum).

We developed an efficient procedure for transformation and regeneration of L. esculentum cv. Moneymaker from cotyledon explants. The effect of two parameters on the transformation frequency was investigated in detail. The use of feeder layers during cocultivation proved to be critical. In addition, it was found that Agrobacterium strains harbouring a L,L-succinamopine type helper plasmid yielded significantly higher transformation frequencies than those with octopine or nopaline type helper plasmids. The optimized protocol was used to obtain transformation frequencies averaging 9%. Of the plants produced approximately 80% proved to be diploid, of which 67% contained the transgene(s) on a single locus.

Efficient transformation of Arabidopsis thaliana using direct gene transfer to protoplasts.

Direct gene transfer has proved to be an efficient transformation method for Arabidopsis thaliana, a member of the Brassicaceae. Transgenic Arabidopsis plants resistant to hygromycin B have been regenerated from mesophyll protoplasts treated with polyethylene glycol and plasmid DNA carrying the hygromycin phosphotransferase (HPT) gene under the control of the 35 S promoter of cauliflower mosaic virus. The transformation procedure reproducibly yields transformants at frequencies of approximately 1 x 10(-4) (based on the number of protoplasts treated) or 5% (based on the number of regenerating calli). DNA from plants regenerated from hygromycin resistant colonies was analysed by Southern blot hybridization demonstrating that the foreign gene is stably integrated into the plant chromosome. Genetic analysis of several hygromycin resistant plants showed that the HPT gene is transmitted to the progeny. Transformation experiments performed with a selectable and a non-selectable gene on separate plasmids resulted in a co-transformation rate of functionally active copies in about 25% of the transformants analysed. Hence this approach can be used to introduce non-selectable genes into the Arabidopsis genome.