Hairy roots were produced following the cc-cultivation of Agrobacterium rhizogenes cells with hypocotyls of five varieties of Antirrhinum majus. The use of a strain containing a binary plasmid with T-DNA bearing the beta-glucuronidase reporter gene resulted in the co-transformation of some root clones. Regeneration of shoots from hairy roots occurred only with variety Golden Monarch. Regenerated plants, some of which were GUS-positive, exhibited the abnormal morphology common among hairy root regenerants; they were dwarfed, had an altered leaf shape, a poor root system and were very delayed in their flowering. Attempts to allow segregation of the two introduced T-DNAs during crossing of primary co-transformants with wild-type plants were not successful since all GUS-positive progeny possessed the abnormal morphology. However, 'semi-dwarf' plants with morphology much more similar to wild-type were produced by the vegetative propagation of selected side-shoots from the transformants.

Hairy roots were produced following the co-cultivation of Agrobacterium rhizogenes cells with hypocotyls of five varieties of Antirrhinum majus. The use of a strain containing a binary plasmid with T-DNA bearing the β-glucuronidase reporter gene resulted in the co-transformation of some root clones. Regeneration of shoots from hairy roots occurred only with variety Golden Monarch. Regenerated plants, some of which were GUS-positive, exhibited the abnormal morphology common among hairy root regenerants; they were dwarfed, had an altered leaf shape, a poor root system and were very delayed in their flowering. Attempts to allow segregation of the two introduced T-DNAs during crossing of primary co-transformants with wild-type plants were not successful since all GUS-positive progeny possessed the abnormal morphology. However, 'semi-dwarf' plants with morphology much more similar to wild-type were produced by the vegetative propagation of selected side-shoots from the transformants.

We have developed a homologous transformation system for the wheat-pathogenic fungus Septoria nodorum based on a benomyl-(MBC-) resistant allele of the beta-tubulin gene. The beta-tubulin gene was isolated by heterologous hybridization from a cosmid library prepared from an MBC-resistant mutant. Cosmids carrying the gene conferred MBC resistance when introduced into a sensitive strain, demonstrating that resistance to MBC fungicides in S. nodorum may be determined by the beta-tubulin gene. This MBC resistant allele of the beta-tubulin gene (tubA(R)) was subcloned into pUC18 and used as a dominant selectable marker for transformation of wild-type sensitive strains. Transformants arose at frequencies of approximately 5 per mu-g of DNA, were integrative in nature and were mitotically stable. Some transformants showed a marked reduction in vigour, both in the presence and absence of MBC; this is thought to arise from overproduction of beta-tubulin. The S. nodorum tubA(R) gene also conferred MBC resistance on the related species Leptosphaeria maculans, a pathogen of Brassica, following its introduction by cotransformation. Probing digested S. nodorum DNA with tubA(R) at low stringency revealed only a single beta-tubulin gene. We anticipate that tubA(R) will prove a useful tool for the investigation of the pathogenicity of S. nodorum and other fungi.

Septoria nodorum has been cotransformed with a number of DNA species. Transformants were selected for resistance to hygromycin B conferred by plasmid pAN7-1. When a second vector (pBT6, pAN5-41B or λ) was included in the transformation experiments, approximately 50% of the hygromycin-resistant transformants had expressed and/or integrated this unselected DNA. Plasmid pBT6 cotransformed Septoria to MBC-resistance by expression of a benomyl-resistant allele of the Neurospora crassa β-tubulin gene (tub-2). Endogenous β-galactosidase in S. nodorum was found to be repressed by growth on sucrose and this allowed the detection of cotransformants expressing a translational fusion between the Aspergillus nidulans gpd gene and the Escherichia coli lazZ gene, carried by the plasmid pAN5-41B. Unlike the presence of the two unselected vectors mentioned above, the presence of wild-type λ-DNA in cotransformation experiments lowered the frequency with which hygromycin-resistant transformants appeared. However, 50% of these were still found to have been cotransformed following Southern hybridization analysis. These high cotransformation frequencies are consistent with previous reports for Septoria and other fungal species and are suggestive of the presence of a small subpopulation of competent protoplasts.

The phytopathogenic fungus Septoria nodorum has been transformed using a plasmid (pAN7-1) containing the Escherichia coli hygromycin phosphotransferase gene (hph). Large, stable hygromycin-resistant transformant colonies appeared at frequencies between 2 and 25 per μg DNA when wheat-adapted and barley-adapted wild type strains were used as recipients. These transformants grew at hygromycin concentrations up to ten times that which inhibits the wild types. A second type of colony also developed on transformation plates. These appeared at higher frequencies, grew less vigorously and could not be subcultured in the presence of hygromycin. They are believed to be abortive transformants. Southern hybridization analyses indicated that transformation takes place via the integration of plasmid DNA into the fungal chromosomal DNA. Multiple integrations occur producing tandemly iterated arrays of plasmid molecules. Some transformants arose as heterokaryons. These could be resolved by propagation through a single spore and transformants purified in this way remained mitotically stable. All of 1,025 transformants tested were unchanged in pathogenicity. Reisolates from leaves retained their hygromycin-resistance, indicating that transformants remain stable during growth in plant tissue. Cotransformation of an unselected plasmid (p3SR2) carrying the Aspergillus nidulans amdS gene occurred at a high frequency.

A case is presented of a 16-month-old white boy with a communication or tunnel between the right sinus of Valsalva and the outflow tract of the left ventricle. The presence of a murmur at birth and the subsequent clinical course suggest that the tunnel was congenital. The physical, electrocardiographic, phonocardiographic, and aortographic findings were quite similar to those of “aortico-left ventricular tunnel” as described by Levy et al.1 The tunnel was occluded surgically, but failure to appreciate the presence of severe aortic stenosis contributed to a fatal outcome.Postmortem study was carried out, and the relationship of the findings of aortico-left ventricular tunnel to aneurysm of the sinuses of Valsalva and the Marfan syndrome is briefly discussed.

A DEVICE FOR THE MEASUREMENT OF PRESSURE AND INJECTION TIME OF CONTRAST SUBSTANCE THROUGH CATHETERSL. B. BEENTJES, PH.D., ROBERT N. COOLEY, M.D. and RICHARD W. BROWN, R.T.Audio Available | Share

* This work was supported by Public Health Service Grant A-4542. t From the Department of Radiology, University of Texas Medical Center, Galveston, Texas. A limited use of mesenteric arteriography suggests that it is helpful in the diagnosis and elucidation of some aspects of the pathology of malignant and benign tumors of the bowel,1~3 in ulcerative colitis,l diverticulitis,2~ 3 the location of intestinal bleeding,4 and rarely in mesenteric arterial obstruction. 5 Contrast substance may be introduced into the superior mesenteric artery via a catheter inserted through a peripheral artery, such as the femoral or brachial, and manipulated into the superior mesenteric artery,6, or through a catheter or needle inserted at the time of operation2-4 into a particular branch serving the segment of bowel in which abnormality is observed or suspected. The amount of contrast substance necessary in segmental injections is obviously less than where the substance is placed in the main artery. Several reports8&dquo;1° indicate that the inadvertent injection of contrast substance into the superior mesenteric artery at the time of abdominal aortography may produce necrosis with perforation of the related intestine necessitating operative intervention, and in at least 2 instances, resulting in death. In other instances the damage, although severe, was reversible, and recovery ensued. On the other hand, numerous inadvertent injections of contrast substance into the superior mesenteric artery did not produce detectable damage.8 Odman’ found no injury following 27 injections of 15 to 20 cc of 45 to 60 °~o Urografin (Renografin) into the superior mesenteric arteries of patients. However, Grayson et al.,ll using dogs, found a high incidence of muscle and mucosal necrosis following the segmental (direct exposure) injection of 25 and 50 % Miokon in amounts as little as 4 cc. A lesser but similar reaction was found with Hypaque 50% and no significant reaction was found under the same circumstances using 60 to Renografin. The present study was carried out in order to

For this study, 22 male and female mongrel dogs were used. Difforent lesions were created surgically in the animals, so that subsequently they might be studied with the multiple film method. The dogs were divided into 5 categories according to the operations performed on them: Group I (5 dogs), wedge resections; Group II (5 dogs), segmental and subsegmental artery constriction; Group III (5 dogs), cortex constriction ; Group IV (5 dogs), lower pole constriction ; and Group V (2 dogs), complete constriction of the renal vein.

From 574 patients with carcinoma of the colon, 111 anastomotic sites have been reviewed. After 3 months the appearance of the colonic anastomosis is well stabilized. The first postoperative barium enema examination will serve as a baseline appearance for future comparison and should be done approximately 3 months following surgery. The distinction between a normal anastomosis and a recurrence may hinge upon the demonstration of minor changes of length of narrowing or caliber of lumen. The high incidence of second, new primary lesions must alert the radiologist to a meticulous examination of the entire remaining colon. Limited air barium contrast studies will provide the sharpest roentgenograms of the anastomosis on the left side.

Elective visualization of branches of the aorta can be obtained by injecting contrast substance through a catheter placed in or near the selected artery. We began our experimental work with available intracardiac catheters. Using dogs, we promptly convinced ourselves that success hinges upon fluoroscopic visualization of a catheter tip having the proper curve. Moulded radiopaque catheters met these requirements. Preparation of Catheter: Catheter design needs to be individualized. Disposable catheters (KIFA) may be bent, punched, and sealed to meet the anticipated needs (4). The proper bend is obtained by heating the catheter containing the stylet over a steam bath (176° F.) and cooling in running water while maintaining the arc. Slight heating of the adaptor end will cause it to curl, facilitating the development of the collar. The flanging tool will finish the seat for the Luer-Lok adaptor. Sterilization may be accomplished by immersion in germicidal solutions or fumigation at 140° F. for three hours in ethylene oxide. Before the introduction of the catheter it should be thoroughly irrigated with sterile saline as well as rinsed externally. Lubrication with sterile mineral oil may facilitate its passage. Introduction of Catheter: The essential features for open exposure were developed by one of us (J. D.) following the observation that large needle punctures of arteries produced complications. Ödman's (2) report of 58 per cent incidence of minor complications with the percutaneous femoral route reinforced our determination to continue this method. The artery is exposed under local anesthesia and the adventitia stripped. Umbilical tape is looped about the vessel above and below the site for introduction of the catheter to regulate bleeding. It is important to exclude collaterals. The distal artery is injected with 0.2 per cent heparin solution. A short transverse incision is then made in the artery, the proximal tape is loosened, and the catheter containing the stainless steel stylet is advanced gently to the approximate origin of the desired vessel. With removal of the stylet, the curve at the tip is largely restored. A 30-c.c. syringe containing normal saline with 0.2 per cent heparin is attached to the catheter. It is usually fairly easy to control the bent tip with external rotation and to visualize fluoroscopically entry into the selected vessel. During injection the tip should not be in the artery. When the catheter is removed, continuous suction is maintained to insure removal of any tiny clots. The artery is repaired with 6–0 arterial silk. Visualization of Vertebral and Carotid Arteries: The catheter may be introduced through the brachial artery and placed near the origin of the vertebral and common carotid so that visualization of these vessels is distinct. Fluoroscopic control of the catheter is highly recommended.