The effect of ethylenediamine chemical modification of plastocyanin on the rate of cytochrome f oxidation and P-700+ reduction.

Chemical modification of plastocyanin was carried out using ethylenediamine plus a water-soluble carbodiimide, which has the effect of replacing a negatively charged carboxylate group with a positively charged amino group at pH 6-8. The conditions were adjusted to produce a series of singly and doubly modified forms of plastocyanin. Differences in charge configuration allowed separation of these forms on a Pharmacia fast protein liquid chromatograph using a Mono Q anion exchange column.

Role of bronchoalveolar lavage in the assessment of opportunistic pulmonary infections: utility and complications.

We prospectively evaluated the diagnostic role of bronchoalveolar lavage in the assessment of opportunistic pulmonary infections and the incidence of associated complications in 100 immunocompromised patients during a 9-month period. Bronchoalveolar lavage was useful in detecting the presence of Pneumocystis carinii, viruses, fungi, bacteria, and mycobacteria in the lower respiratory tract. P.

Determination of the redox potential and diffusion coefficient of the protein plastocyanin using optically transparent filar electrodes.

Direct and mediated electrolysis of the protein plastocyanin at a gold filar electrode is described. The filar electrode used is of a unique design that allows potentiometric measurements, steady-state voltammetry and absorption spectrophotometry to be performed on a few microliters of solution containing 0.1-1.

Lung cancer screening: the Mayo program.

The National Cancer Institute has sponsored three randomized controlled trials of screening for early lung cancer in large, high-risk populations to determine whether lung cancer detection can be improved by adding sputum cytological screening every 4 months to chest roentgenography done either yearly or every 4 months; and lung cancer mortality can be significantly reduced by this type of screening program, followed by appropriate treatment. Results of the three trials suggest that sputum cytology alone detects 15% to 20% of lung cancers, almost all of which are squamous cancers with a favorable prognosis; and chest roentgenography may be a more effective test for early-stage lung cancer than previous reports have suggested. Nevertheless, results of the randomized trial conducted at the Mayo Clinic showed that offering both procedures to high-risk outpatients every 4 months conferred no mortality advantage over standard medical practice that included recommended annual testing.

pH dependent conformational changes and electrostatic effects in plastocyanin.

Reduction of plastocyanin (PC) caused a change in the electric field at the surface of the molecule which resulted in a 0.3 pH unit increase in the pKa of a nitrated derivative of Tyr 83. This change in electrical potential could alter the affinity for cytochrome f which is known to bind at this site.

Kinematic features of wheelchair propulsion.

Three male paraplegics volunteered to push their wheelchairs on a motor driven treadmill, for a total of 80 min each, at a work rate of 60-65% of their VO2 maximum, determined on an earlier test session. At 20 min intervals 16 mm high-speed film of the subjects was taken for three consecutive push cycles. The digitized film was used to compute the angular kinematics of the shoulder and elbow joints, the variations in the position of the trunk (as measured by a marker on the neck) and hand relative to the axle of the rear wheel.

Early lung cancer detection: results of the initial (prevalence) radiologic and cytologic screening in the Mayo Clinic study.

The initial (prevalence) radiologic and cytologic screening for lung cancer in the Mayo Clinic study (Mayo Lung Project) involved 10,933 outpatients. All were men at high risk for lung cancer, but none were suspected of having it when they entered the Mayo Clinic. Screening identified 91 lung cancers (8.

Muscle Balance between Hamstrings and Quadriceps during Isokinetic Exercise.

The maximum flexor and extensor peak torques about the knee joint of 17 male and 17 female subjects were determined using a CYBEX isokinetic dynamometer. These values were used to evaluate the influence of changing joint angular-velocity on the ratio of peak hamstrings torque to peak quadriceps torque. Additionally, an assessment of the influence of gravity on the recorded peak torques, and thus the ratio, was made Values for the flexion-extension ratio corrected for gravity were found not significantly different at the measured joint angular-velocities whereas the values of the ratio not corrected for gravity were found significantly different at increasing joint angular-velocities It is necessary that the physiotherapist recognize the importance of the influence of gravity when recording forces developed in the vertical plane.

Roentgenographically occult lung cancer: pathologic findings and frequency of multicentricity during a 10-year period.

During the first 10 years of the Mayo Lung Project, 68 roentgenographically inapparent ("occult") lung cancers were localized and apparently completely resected. A pathologic classification was developed based on depth of tumor infiltration. The five categories were (1) in situ carcinoma confined to surface epithelium or ducts of mucous glands or acini (23 cancers), (2) intramucosal invasion not greater than 0.

Neuromuscular electrical stimulation for the head-injured patient.

Recent research has shown that electrical stimulation is effective in treatment programs designed to maintain or gain range of motion, to facilitate voluntary motor control, and to strengthen muscles weakened by disuse. All of these treatment goals are relevant to the head-injured patient who frequently demonstrates profound disuse atrophy, joint contractures with excessive muscle tone, and decreased voluntary motor capabilities. As the cognitive status of the head-injured patient improves, electrical stimulation can be incorporated into traditional treatment programs to enhance their effectiveness.

Interstitial lung disease. Assessment by bronchoalveolar lavage.

Bronchoalveolar lavage is a new bronchoscopic technique that permits assessment of changes in the cellular traffic in the alveolar spaces. During a 16-month period, 120 patients underwent bronchoalveolar lavage at our institution. Control subjects (N = 11) had a predominance of alveolar macrophages (94 +/- 1%) with a few lymphocytes (4 +/- 1%), whereas 35 patients with idiopathic pulmonary fibrosis had a substantial increase in the number of polymorphonuclear leukocytes (17 +/- 2%), and 32 patients with sarcoidosis had an appreciable increase in the number of lymphocytes (27 +/- 2%).

Roentgenographically occult lung cancer. A ten-year experience.

During the past 10 years, 54 patients, all men, were found to have roentgenographically occult lung cancer. The mean age was 61 years (range 45 to 76 years). All patients had abnormal findings on sputum cytologic study (carcinoma in 41 patients and squamous cell atypia in 13).

Lung cancer detected during a screening program using four-month chest radiographs.

Ninety-two lung cancers were detected in the Mayo Lung Project in patients undergoing chest radiography every four months for screening. Fifty patients had a peripheral nodule, 16 had a perihilar nodule, 20 had hilar or mediastinal enlargement, and six had pneumonitis. The peripheral cancers grew slowly.

Clinical utility of bronchoalveolar lavage in the assessment of interstitial lung disease.

Bronchoalveolar lavage is a new bronchoscopic technique which permits assessment of changes in the cellular traffic in the alveolar spaces. One hundred and fourteen patients underwent bronchoalveolar lavage at the Mayo Clinic during a 16-month period. Whereas control subjects had a predominance of alveolar macrophages (93 +/- 1%) with few lymphocytes (5 +/- 1%), 35 subjects with idiopathic pulmonary fibrosis had a marked increase in the number of polymorphonuclear leukocytes (17 +/- 2%), and 32 subjects with sarcoidosis had a marked increase in the number of lymphocytes (26 +/- 2%).