Clinical and Molecular Characterization of Patients with Distal 11q Deletions

Jacobsen syndrome is caused by segmental aneusomy for the distal end of the long arm of chromosome 11. Typical features include mild to moderate psychomotor retardation, trigonocephaly, facial dysmorphism, cardiac defects, and thrombocytopenia, though none of these features are invariably present. To define the critical regions responsible for these abnormalities, we studied 17 individuals with de novo terminal deletions of 11q. The patients were characterized in a loss-of-heterozygosity analysis using polymorphic dinucleotide repeats. The breakpoints in the complete two-generation families were localized with an average resolution of 3.9 cM. Eight patients with the largest deletions extending from 11q23.3 to 11qter have breakpoints, between D11S924 and D11S1341. This cytogenetic region accounts for the majority of 11q⁻ patients and may be related to the FRA11B fragile site in 11q23.3. One patient with a small terminal deletion distal to D11S1351 had facial dysmorphism, cardiac defects, and thrombocytopenia, suggesting that the genes responsible for these features may lie distal to D11S1351. Twelve of 15 patients with deletion breakpoints as far distal as D11S1345 had trigonocephaly, while patients with deletions distal to D11S912 did not, suggesting that, if hemizygosity for a single gene is responsible for this dysmorphic feature, the gene may lie distal to D11S1345 and proximal to D11S912.     

Phosphinothricin stimulates somatic embryogenesis in grape (Vitis sp. L.)

The effect of phosphinothricin concentration on embryo production from an embryogenic callus of Chancellor (Vitis L. complex interspecific hybrid) was tested. Embryogenic callus was cultured on medium supplemented with nine phosphinothricin concentrations (0, 0.1, 0.5, 1, 1.5, 2, 3, 5, and 10 mg/l). The highest number of embryos per plate was observed at 0.5 mg/l phosphinothricin. The use of phosphinothricin to stimulate embryo production did not affect embryo germination and plantlet formation. Three germination techniques were compared. Embryo dehydration or growth on Transfergelsolidified medium gave higher germination rates than chilling treatments. Most germinated somatic embryos produced secondary embryos from the hypocotyl after a few weeks of culture. Regardless of the germination technique, the plantlet conversion rate was very low.Abbreviations AC activated charcoal - 2,4-D 2,4-dichlorophenoxyacetic acid - BA 6-benzylaminopurine - MS Murashige and Skoog (1962) basal medium - NN Nitsch and Nitsch (1969) medium - PPT phosphinothricin     

Identification of tomato bushy stunt virus in cherry and plum trees showing fruit pitting symptoms

The fruit pitting symptoms on cherries, plums and prunes were investigated from the standpoint of their etiology. Tomato bushy stunt virus (TBSV) was isolated from pitted fruits of these plants and from their leaves and identified by means of biological and serological methods. Both isolates reacted with antisera againstPetunia and artichoke strain of this virus. In addition, the etiology of pseudopox disease of plum and that of cherry detrimental canker is discussed.     

Purification and properties of arabis mosaic and tomato bushy stunt viruses isolated from lilac (Syringa vulgaris L.)

The paper gives more detailed characteristics of Arabis mosaic virus (AMV) and tomato bushy stunt virus (TBSV) isolated from lilac, the latter being identified in lilac (from plants suffering from yellow ring disease) for the first time. The isolate of TBSV from lilac, from which an antiserum with a titre of 1024 was prepared, is closely related to the artichoke strain. Information is given about two types of ringspot disease and about chlorotic ringspot of lilac. Whereas in the leaves of lilac suffering from ringspot disease (of ring mosaic type) the presence of AMV was demonstrated, the sap transmission from the leaves diseased with ringspot of linepattern (and wave-like mosaic) type failed; from the leaves affected by chlorotic ringspot a mixture of AMV and cherry leaf roll virus was identified. In addition, the polyetiological nature of “spring” mosaic and necrotic mosaic of lilac, in which bacteriumPseudomonas syringae van Hall, was found is dealt with. The TBSV was also identified in the isolate of necrotic mosaic.Additional index words: Lilac ringspot, chlorotic ringspot, yellow ring, “spring” mosaic, necrotic mosaic, cherry leaf roll virus,Pseudomonas syringae van Hall.     

Isolation and characterization of DNA sequences from Triticum aestivum which function as origins of replication in Saccharomyces cerevisiae

Recombinant YIp5 plasmids with the DNA from Triticum aestivum are capable of autonomous replication in Saccharomyces cerevisiae. The URA transformants are unstable without selection pressure, and transformation of yeast cells with these plasmids occurs at high frequency. The cloned sequences were characterized and analyzed to state their belonging to Triticum tribe.     

Chronic and acute effects of thyrotropin on phosphatidylinositol turnover in cultured porcine thyroid cells

The 32P incorporation into phospholipids of isolated porcine thyroid cells, cultured for 1-4 days, has been studied in subsequent 2-h incubations. Along with culture ageing, decreased 32P incorporation into total phospholipid of control cells was observed. The presence of 40 munits/ml TSH during the 2 h incubation yielded a relative increase in labelling of phosphatidylinositol, named 'acute phospholipid effect'. A chronic treatment of the cells with TSH concentration ranging from 0.1 to 10 munits/ml ensured the maintenance of a high turnover rate of total phospholipids. The analysis of individual phospholipids revealed that 1-day culture cells in the presence of 0.1 munits/ml TSH presented a strong increase of phosphatidylinositol labelling. This 'chronic phospholipid effect' of TSH can be reproduced by a chronic treatment with dibutyryl cyclic AMP (10(-3)M) or prostaglandin E2 (10(-6)M), which did not evoke a classical phospholipid effect in a 2 h incubation. If TSH (40 munits/ml) is added to the cells in a 2 h incubation, control cells show the classical phospholipid effect whereas cells chronically treated with TSH, dibutyryl cyclic AMP or prostaglandin E2 presented a 'reverse phospholipid effect' i.e. a relative decrease in phosphatidylinositol labelling. 10(-4)M cycloheximide presence during the last 12 h of culture prevented the establishment of the 'chronic phospholipid effect' and of its consequence, 'the reverse phospholipid effect'. On the basis of these results a scheme is proposed in keeping with current hypotheses concerning phosphatidylinositol metabolism.     

Kininogen and Kinin in Experimental Spinal Cord Injury

Activation of the kallikrein-kinin system has been implicated in the pathogenesis of vasogenic brain edema and posttraumatic vascular injury. We determined the levels of kininogen and kinin in an experimental spinal cord injury model in the rat. Kininogen content in traumatized cord segments increased in a time-dependent manner. Western blot analysis showed that the kininogen in traumatized cord comigrates with 68K low-molecular-weight kininogen or T-kininogen. Trypsin treatment of the kininogen in traumatized cord released both bradykinin and T-kinin, which were separated by HPLC and quantified with a kinin radioimmunoassay. Endogenous kinin levels in the frozen spinal cord also increased up to 40-fold 2 h after injury as compared with controls. The results demonstrate an increased accumulation of kininogen and its conversion to vasoactive kinins in experimental spinal cord injury.