Agrobacterium mediated genetic transformation and plant regeneration via organogenesis and somatic embryogenesis from cotyledon leaves in eggplant (Solanum melongena L. cv. ‘Kecskeméti lila’)

Summary Novel and efficient protocols for plant regeneration and genetic transformation from longitudinally-halved cotyledons ofin vitro raised seedlings in eggplant (Solanum melongena L.) are described. After co-cultivation withAgrobacterium vectors harboring neomycin phosphotransferase (nptll) as selectable marker, transgenic plantlets were regenerated on selective media containing 100 mg/l kanamycin. Transformants were recovered from embryogenic calli induced by 4 mg/l-naphthaleneacetic acid (NAA), and from organogenic calli induced by the addition of 2 mg/l zeatin plus 0.01 mg/l NAA. Nineteen independent transgenic lines were grown to maturity. The structural integrity, expression and sexual transmission of the introduced genes for neomycin phosphotransferase and ß-glucuronidase (gus) were investigated.     

A new mutation protocol for obtaining auxotrophic mutants of the yeastPhaffia rhodozyma

Summary A new mutation strategy, which involves -irradiation of cells followed by a selective enzymatic enrichment step, was worked out to obtain auxotrophic mutants from the astaxanthin-producing yeast P. rhodozyma. Under the optimized conditions described, different mutants suitable for strain improvement were isolated.     

Clinical, enzymological and histological changes in chronic diffuse liver diseases following (+)-cyanidanol-3 (Catergen) treatment

The effect of (+)-cyanidanol-3 (Catergen) monotherapy was examined in 18 patients with alcoholic liver disease and in 12 patients with chronic active hepatitis. During the administration of the drug the majority of complaints diminished or ceased in both groups. In patients with alcoholic liver disease bromsulphalein retention and gamma glutamyl transferase levels decreased, in chronic active hepatitis serum glutaminic pyruvic acid transaminase (SGPT) and alkaline phosphatase levels increased, pseudocholinesterase level decreased. The histological abnormalities of alcoholic liver injury improved in the majority of cases, on the other hand, it was deteriorated in two third of the cases with chronic active hepatitis. In two cases the histological recovery of acute alcoholic hepatitis was observed. On the basis of this results we conclude that Catergen has an excellent therapeutic effect in alcoholic liver injury while in chronic active liver diseases it can be applied only as a part of combined therapy.     

A comparative dynamic study of the effectiveness of gastric cytoprotection by vitamin A, De-Nol, sucralfate and ulcer healing by pirenzepine in patients with chronic gastric ulcer (a multiclinical and randomized study)

The gastric cytoprotective effects of vitamin A, De-Nol and sucralfate were compared with the effectiveness of pirenzepine in healing ulcer in patients with chronic gastric ulcer. A total of 100 patients was randomized into different groups: the patients were treated with antacids, vitamin A (3 X 50.000 IU), De-Nol liquid (4 X 5 ml), sucralfate (4 X 1 g) or pirenzepine (3 X 50 mg). The treatment was continued for 4 weeks. At the beginning, 2 and 4 weeks after starting treatment the patients were subjected to endoscopy and the size of the ulcer was measured planimetrically. The ulcer-healing effect of De-Nol liquid was significantly better than that of the antacids (p less than 0.01). Ulcer size was reduced significantly in all groups (p less than 0.01), however, at the end of the study the gastric ulcers were smallest in the De-Nol treated group (p less than 0.001). The dynamics of ulcer healing in the second week was most favourable in the patients receiving vitamin A (p less than 0.01). The present data point to the cytoprotective effects of De-Nol liquid, vitamin A and sucralfate and to their ability of healing chronic gastric ulcers.     

Evidence for the existence of gastric cytoprotective effect of atropine and cimetidine in humans

The effects of cimetidine (12.5 mg i.m.) and atropine (0.125 mg i.m.) were studied on the basal (BAO) and pentagastrin (6 micrograms X kg-1 s.c.)-stimulated (MAO) gastric acid secretion; the gastric mucosal microbleeding provoked by one-day treatment with indomethacin (4 X 25 mg orally) in patients with chronic disorders of the joints. The extent of the gastric microbleeding was measured by spectrophotometric determination of haemoglobin in gastric lavage fluid. The aims of this study were to determine the doses of cimetidine and atropine in humans without any significant inhibitory effects either on the basal or on the maximal gastric acid output to evaluate the cytoprotective action of these doses of cimetidine and atropine on the indomethacin-induced gastric microbleeding in the man. It was found that cimetidine (12.5 mg i.m.) and atropine (0.125 mg i.m.) did not cause any significant inhibition either of the BAO or of the MAO; indomethacin (4 X 25 mg orally) significantly increased gastric microbleeding in the patients; cimetidine and atropine, in the above doses, were able to prevent significantly indomethacin-induced gastric microbleeding in the patients. These results provide evidence for the existence of gastric cytoprotective effects of cimetidine and atropine in humans.     

Studies on purine transport and on purine content in vacuoles isolated from Saccharomyces cerevisiae

The transport of purine derivatives into vacuoles isolated from Saccharomyces cerevisiae was studied. Vacuoles which conserved their ability to take up purine compounds were prepared by a modification of the method of polybase-induced lysis of spheroplasts.Guanosine > inosine = hypoxanthine > adenosine were taken up with decreasing initial velocities, respectively; adenine was not transported.Guanosine and adenosine transporting systems were saturable, with apparent K_m values 0.63 mM and 0.15 mM respectively, while uptake rates of inosine and of hypoxanthine were linear functions of their concentrations.Adenosine transport in vacuoles appeared strongly dependent on the growth phase of the cell culture.The system transporting adenosine was further characterized by its pH dependency optimum of 7.1 and its sensitivity to inhibition by $\text{S-}\text{adenosyl-}\text{l}\text{-methionine}$.In the absence of adenosine in the external medium, [¹⁴C]adenosine did not flow out from preloaded vacuoles. However, in the presence of external adenosine, a very rapid efflux of radioactivity was observed, indicating an exchange mechanism for the observed adenosine transport in the vacuoles.In isolated vacuoles the only purine derivative accumulated was found to be $\text{S-}\text{adenosyl-}\text{l}\text{-homocysteine}$.     

In vitro dissociation-recombination of malate dehydrogenase subunits in Corydalis solida

Summary Two allelic forms of NAD specific malate dehydrogenase were found in samples of a wild population of Corydalis solida. The dimeric nature and the origin of the heterodimeric form has been demonstrated by in vitro dissociation and recombination of the subunits detected by subsequent electrophoresis. The method is applicable for polyacrylamide gel electrophoresis of crude leaf extracts of individual MDH isozyme forms.     

Antigen-binding receptors on T cells from long-term MLR. Evidence of binding sites for allogeneic and self-MHC products

Antibody inhibition of radiolabelled stimulator membrane vesicle binding by T blasts activated in the mixed lymphocyte reaction (MLR) was used to identify responder-cell determinants involved in the binding phenomenon. Antisera or monoclonal antibodies against Thy-1, Lyt-1, Lyt-2 and Ly-6 antigens were not inhibitory. However, antibodies against heavy-chain V region (V_H) determinants strongly inhibited vesicle binding by both primary and longterm MLR blasts. Anti-Ia (both alloantisera and monoclonal reagents) caused inhibition of antigen binding by primary MLR blasts only. T blasts from long-term MLR lines were neither Ia-positive, nor susceptible to blocking of antigen binding with anti-Ia. However, these cells were capable of specifically absorbing soluble syngeneic Ia material, with the concomitant appearance of vesiclebinding inhibition with anti-Ia sera. Acquisition of syngeneic Ia by T blasts was effectively blocked with the anti-V_H reagent. Passively bound self-Ia did not interfere with vesicle binding in the absence of anti-Ia. These results strongly suggest the existance of specific self-Ia acceptor sites closely linked to the receptors for stimulator alloantigens on T cells proliferating in MLR. A receptor model based on these findings is briefly discussed.Abbreviations used in this paper B10 C57BL/10 - Con A concanavalin A - FcR Fc receptor - FCS fetal calf serum - H heavy chain - Ia I-region associated antigen - Ig immunoglobulin - LPS lipopolysaccharide - Lyt T-lymphocyte differentiation antigen - MHC major histocompatibility complex - MLR mixed lymphocyte reaction - PM plasma membrane - T thymus derived - Tcr T-cell receptor - V variable region of Ig     

Genetic control of T-cell proliferative responses to poly(glu40ala60) and poly(glu51lys34tyr15): subregion-specific inhibition of the responses with monoclonal Ia antibodies

The relationship between Ir genes and Ia antigens was studied in the T-cell proliferative responses to two synthetic polypeptides poly(glu40ala60) (GA) and poly(glu51lys34tyr15) (GLT15). The response to GA was found to be controlled by an Ir gene in the I-A subregion, whereas the anti-GLT15 response was shown to be under dual control, one Ir gene mapping probably in the I-A subregion, and the other in the I-E subregion. We obtained two different lines of evidence suggesting identity of Ir and Ia genes. First, the presence of certain serologically identified allelic forms of the I-A-encoded A molecule correlated with the responder status to GA both in inbred strains and in B10.W lines, the latter carrying wild-derived H-2 haplotypes. Thus the Ir and Ia phenotypes were not separable in strains of independent origin. Second, the anti-GA response was completely inhibited by monoclonal antibodies against determinants on the A molecule (Ia.8, 15, and 19), but not by a monoclonal antibody against a determinant on the E molecule (Ia.7). In contrast, the anti-GLT15 response was only inhibited by a monoclonal antibody against the E molecule, but not by antibodies against the A molecule. Our data support the hypothesis that Ia antigens, as restriction elements for T-cell recognition, may in fact be the phenotypic manifestation of Ir genes.