Agrobacterium tumefaciens induces cancerous growths called crown galls at wound sites on dicotyledonous plants. A large plasmid called T1 plasmid is responsible for virulence. Upon tumor induction, part of the plasmid, termed T-DNA, becomes integrated into plant genome and its genetic sequences are expressed. These properties allow T1 plasmids to be used as gene vectors in plants. Several in vitro methods for the transfer of T1 plasmid into plant cell have been developed. One of them is the treatment of bacterial spheroplasts and plant protoplasts mixture with polyethylene glycol that is generally used as fusogen in cell-to-cell fusion. Several workers investigated the interaction of bacterial spheroplasts with plant protoplasts in the presence of polyethylene glycol and suggested that the interaction is not fusion but endocytosis. In this report we observed the interaction of Agrobacterium tumefaciens spheroplasts with Nicotiana tabacum protoplasts by electron microscope. Agrobacterium tumefaciens spheroplasts with Nicotiana tabacum protoplasts were prepared and mixed in the presence of polyethylene glycol and high pH-high Ca²⁺ buffer. Then the interaction of the spheroplasts with the protoplasts was examined by transmission electron microscope. After the treatment of polyethylene glycol the spheroplasts adhered to the surface of the protoplasts and then they were engulfed by the protoplasts. After the high pH-high Ca²⁺ buffer treatment the engulfed spheroplasts lost their cell integrity. No fusion process was observed. Thus all these observation suggest that the introduction process of Agrobacterium tumefaciens spheroplasts into Nicotiana tabacum protoplasts with the aid of polyethylene glycol is endocytosis.
Agrobacterium tumefaciens* ; Agrobacterium* ; Endocytosis ; Genome, Plant ; In Vitro Techniques ; Plant Cells ; Plant Tumors ; Plants ; Plasmids ; Polyethylene Glycols ; Protoplasts* ; Spheroplasts* ; Tobacco* ; Virulence ; Wounds and Injuries

No abstract available.
Humans

No abstract available.

Transient osteoporosis of the hip is a self-limited condition of uncertain etiology and pathogenesis that affects young and middle aged adults. Even its clinical features are similar to the features of osteonecrosis the prognosis and clinical end result are quite different. So differential diagnosis between the two is very important. We present a case of transient osteoporosis of the hip in middle aged man, which was completely reeovered after conservative treatment.
Adult ; Diagnosis, Differential ; Hip ; Humans ; Middle Aged ; Osteonecrosis ; Osteoporosis ; Prognosis

To evaluate the diagnostic accuracy of two-dimensional echocardiogrphy(2-D echo) in ventricular septal defect, location and size of the defects, estimated right ventricular systolic pressure and associated cardiac anomaly were compared to the operative findings in 139 children operated for correction of ventricular septal defect at Severance Hospital from Jan. 1983 to June 1987. In addition, postoperative complications and mortality cases were anlysed. The following results were obtained; 1) Perimembranous defects were 82 cases(66.1%), subarterial infundibular defects 33 cases(26.6%), and muscular defect was found in only 1 case(0.8%). The accuracy of 2-D echo in localizing the defects was 84.2%. 2) In 79.2% of the patients, the defects were moderate to large in size, and actual size measured at operation was larger than that obtained by echocardography in general. 3) The estimated right ventricular systolic pressure was correlated(r=0.650) with that measured at the operating field. 4) Combined cardiac anomalies were patent ductus arteriosus(22 cases), atrial septal defect(3 cases), valvular pulmonic stenosis(2 cases) and interventricular septal aneurysm(2 cases). The sensitivity of 2-D echo in detecting these anomalies was 65.5% and the specificity was 96.4%. 5) Among 32 patients who had postoperative complications, in two thirds, there were pulmonary complication including lung atelectasis(16 cases), pleural effusion(5 cases)and pneumonia(5 cases). 6) Operative mortality was 2.9%(4 cases). The causes of death were low cardiac output state due to left ventricular myocardial failure in 3 patients and respiratory failure from asphyxia in one case. In conclusion, with close cooperation with cardiac surgeons, there will be few problems in diagnosing and operating patients with ventricular septal defect on the basis of two-dimensional echocardiographic findings without invasive procedures, such as cardiac catheterization, even with pulmonary hypertension, unless Eisenmenger syndrome is complicated.
Asphyxia ; Blood Pressure ; Cardiac Catheterization ; Cardiac Catheters ; Cardiac Output, Low ; Catheterization* ; Catheters* ; Cause of Death ; Child* ; Echocardiography* ; Eisenmenger Complex ; Heart Failure ; Heart Septal Defects, Ventricular* ; Humans ; Hypertension, Pulmonary ; Lung ; Mortality ; Postoperative Complications ; Respiratory Insufficiency ; Sensitivity and Specificity

The soil bacterium Agrobacterium tumefaciens is a plant pathogen that causes crown gall tumors by infecting the wounded dicotyledonous plants and subsequent integration of bacterial DNA into plant nuclear DNA. Virulent A. tumefaciens strains harbor a large Ti (tumor–inducing) plasmid that carries genes essential for tumorigenesis. In the present study, 13 strains (Malus pumila Mill; A₁₋₃, Populus monilifera; W₁₋₆, Populus tomentiglandlosa; P₁₋₃ and Rosa species; R₁) of Agrobacterium isolated in korean crown gall tumors and plasmids were observed in 6 strains (W₂, W₃, W₆, P₁, P₃ and A₂). The test for crown gall tumor formation was resulted only in ATCC15955 and KW2 strains inoculated into the stem of sun flower and the development was observed for 4 and 6 weeks after inoculation. Above two Ti plasmids (pTi) were purified by cesium chloride-ethidium bromide density gradient centrifugation and digested with restriction enzyme and fragments of pTiATCC15955 and pTiKW₂ observed by EcoR I ; 25&27, Hind III ; 23&21, BamH I ; each 20 and Hpa I ; 12&27. And sizes of pTiATCC15955 and and pTiKW₂ calculated as 200 and 87 kbases. Octopine was isolated from tumor tissue (W₁₋₆ and P₁₋₃) and these strains confirmed as octopine type.
Agrobacterium tumefaciens ; Agrobacterium* ; Carcinogenesis ; Centrifugation, Density Gradient ; Cesium ; DNA ; DNA, Bacterial ; Flowers ; Korea* ; Plant Tumor-Inducing Plasmids ; Plant Tumors ; Plants ; Plasmids* ; Populus ; Rosa ; Soil ; Solar System ; Wounds and Injuries

Supravalvular aortic stenosis may be defined as an obstructive congenital deformity of the ascending aorta which originates just distal to the level of the origins of the coronary arteries. It may be localized or diffuse, and includes a wide spectrum of pathologic changes. A 16 years old school boy was admitted because of exertional dyspnea for 6 years. Clinical diagnosis of supravalvular and valvular aortic stenosis with bicuspid aortic valves and myocardial hypertrophy was made by echocardiography and angiocardiography. Surgical correction was performed successfully. We presented a case of supravalvular and valvular aortic stenosis with a review of literatures.
Adolescent ; Angiocardiography ; Aorta ; Aortic Stenosis, Supravalvular ; Aortic Valve ; Aortic Valve Stenosis* ; Bicuspid ; Congenital Abnormalities ; Coronary Vessels ; Diagnosis ; Dyspnea ; Echocardiography ; Humans ; Hypertrophy ; Male

No abstract available.
Interleukin-2* ; Interleukins* ; Killer Cells, Natural*

Chondromalacia patella is a symptom complex characterized by aching pain behind the knee cap, retropatella tenderness that is aggravated by the stair climbing. Malalignment is an important factor causing chondromalacia patella. And to recognize it, is important in the diagnosis and treatment. We studied 3 parameters in the chondromalacic knee and nonchondromalacic knee and the following results was obtained. l. In nonchondromalacic knee, the sulcus angle is 141° 7′ and the congruence angle is −5° 1′ 2. In chonduomalacic knee the sulcus sagle is 139° 2′ and the congruence angle is +5° 3′ 3. In the group with abnormal congruence angle, there was much degenerative changes in the patellofemaral joint. So, it can be inferred that chondromalacia is a precursor of the osteoarthritis and the patient with abnormal congruence angle should be treated actively at the early stage if the conservative treatment had failed.
Cartilage Diseases ; Diagnosis ; Humans ; Joints ; Knee ; Osteoarthritis ; Patella ; Sesamoid Bones

Supracondylar fracture of the femur is not as common as the shaft fracture. There is wide range of potential complication in the treatment of these fractures and the method of the treament and the evaluation of it's result is variable and remains controversial. Until 1960, we believed conservative treatment supirior to the operative treatment of the supracondylar fracture of the femur. But recently, anatomical reduction and internal fixation with early joint motion showed satisfactory results and is the trend of treatment of these fracture. The authors of this thesis performed treatment of supracondylar fracture of femur by utilizing Ender nails and screws in 13 cases during the period from October 1987 to November 1988 and it was found that operation was relatively simple, bleeding was little and early exercise of knee was allowed and even for patients of old age internal fixation could be maintained easily.
Femur ; Hemorrhage ; Humans ; Joints ; Knee ; Methods