Isolation and characterization of wheat-rye recombinants involving chromosome arm 1DS of wheat.

The introgression of genetic material from alien species is assuming increased importance in wheat breeding programs. One example is the translocation of the short arm of rye chromosome 1 (1RS) onto homoeologous wheat chromosomes, which confers disease resistance and increased yield on wheat. However, this translocation is also associated with dough quality defects. To break the linkage between the desirable agronomic traits and poor dough quality, recombination has been induced between 1RS and the homoeologous wheat arm IDS. Seven new recombinants were isolated, with five being similar to those reported earlier and two havina new type of structure. All available recombinantsw ere characterized with DNA probes for the loci Nor-R1, 5SDna-R1, and Tel-R1. Also, the amount of rye chromatin present was quantified with a dispersed rye-specific repetitive DNA sequence in quantitative dot blots. Furthermore, the wheat-rye recombinants were used as a mapping tool to assign two RFLP markers to specific regions on chromosome arms 1DS and 1RS of wheat and rye, respectively.

Temporal control of phytochrome-dependent gene expression during radish seedling development.

The level of two nuclear-encoded transcripts (the small subunit of ribulose-1,5-bisphosphate carboxylase and the chlorophyll a/b-binding protein of photosystem II) and two chloroplastencoded mRNAs (the large subunit of ribulose-1,5-bisphosphate carboxylase and the chloroplast 32-kDa polypeptide) were analysed during the first 4 d of radish (Raphanus sativus L.) seedling development. A single 5-min red-light pulse increased the concentrations of all transcripts by various orders of magnitude, depending on the particular mRNA. For all transcripts the maximal effect of the red light was observed when the irradiation was applied 48 h following sowing. The red-light treatment did not lead to changes in the total RNA level or to alterations in the levels of nuclear and chloroplastic DNAs; the level of ß-actin mRNA was also unaffected by the light treatment. It is concluded that during the first days of development, cells of radish cotyledons undergo light-independent molecular changes, occurring at the transcriptional level, conferring on them a transient competence towards the photoreceptor phytochrome.

[Treatment of reflex vagal hypertonia in infants. Role of diphemanil (apropos of 50 cases)]. / Traitement de l'hypertonie vagale réflexe du nourrisson. Place du diphémanil (à propos de 50 cas).

For a period of 20 months, 50 consecutive infants (mean age: 11 months) were given Diphemanil (atropine like synthetic drug) for reflex symptomatic bradycardia of probable vagal origin. Treatment's results were evaluated with the study of oculo-cardiac reflex (OCR) and Holter monitoring performed before and 3 months after the beginning of Diphemanil. If tolerance was generally good, it was not possible to demonstrate the clinical efficacy of the treatment on the whole group. However, assertive success was seen on individual cases. Holter and OCR data improved statistically. The other therapeutical means aiming at warning possible complications of the hypertonic vagal reflex were reviewed: inserting a cardiac pace-maker does not always prevent sudden death; a nodal sinus surgical selective denervation might be justified in certain exceptional cases, because of the severity of the spontaneous evolution or of the resistance to medical treatment.