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Biomedical subjects

T H Johnson

Publications and source records attributed to T H Johnson.

At least 19 recordsLinked to original sources

Marked spontaneous improvement in ejection fraction in patients with congestive heart failure.

PURPOSE: The overall prognosis for patients with congestive heart failure is poor. Defining specific populations that might demonstrate improved survival has been difficult. We therefore examined our patient database for patients with congestive heart failure who demonstrated sustained improvement in left ventricular function and associated resolution of signs and symptoms of congestive heart failure. PATIENTS AND METHODS: We identified 11 patients with severe congestive heart failure (average ejection fraction 21.9 +/- 4.23% (+/- SD) who developed spontaneous, marked improvement over a period of follow-up lasting 4.25 +/- 1.49 years. All 11 patients were initially symptomatic with exertional dyspnea and fatigue for a minimum duration of 3 months. They form a subset of a larger group of 97 patients with chronic congestive heart failure that we have followed with sequential ejection fraction measurements. All 11 patients were treated with digitalis diuretics, and either converting-enzyme inhibitors or a combination of isosorbide dinitrate and hydralazine. Ten of the 11 patients had a history consistent with chronic alcoholism, and each reportedly abstained from alcohol during follow-up. RESULTS: During the follow-up period, the average ejection fraction improved in 11 patients from 21.9 +/- 4.23% to 56.64 +/- 10.22%. Late follow-up indicates an average ejection fraction of 52.6 +/- 8.55% for the group. Congestive heart failure resolved in each case. CONCLUSIONS: We conclude that selected patients with severe congestive heart failure can markedly improve their left ventricular function in association with complete resolution of heart failure. This appears to be particularly evident in those patients with chronic alcoholism who subsequently abstain.

Aged

Relationship of dietary aluminum, phosphorus, and calcium to phosphorus and calcium metabolism and growth performance of broiler chicks.

Dietary treatments providing three levels of added Al (0, .196, or .392%) as aluminum sulfate and of available phosphorus (Pav) .45, .68, or .78%) in a factorial arrangement were administered to day-old chicks in Experiment 1. Plasma inorganic phosphorus (Pi) was significantly (P less than .05) elevated by increasing Pav and was decreased by Al. Body weight gain, feed intake, and the gain:feed ratio at Day 21 were significantly decreased by increased concentrations of Al, but were unaffected by the Pav concentrations. Decreases of 39 and 73% in weight gain and of 34 and 66% in feed intake resulted from feeding .196 and .392% Al, respectively. In Experiment 2, day-old chicks were fed diets supplemented with 0 or .392% Al in combination with .9% Ca plus .45% Pav, .9% Ca plus .78% Pav, 1.8% Ca plus .45% Pav, or 1.8% Ca plus .9% Pav. After 21 days, the supplemental Al resulted in: 1) significantly poorer growth performance; 2) decreased plasma Pi, total Ca, Zn, and Mg; and 3) decreased tibia weight and breaking strength. Elevating Pav improved growth performance, plasma Pi, and tibia weight and strength, and decreased plasma total Ca. Increasing dietary Ca significantly decreased plasma Pi and increased plasma total Ca without affecting other parameters. Increasing Pav alleviated the negative effect of Al on plasma Pi without correcting the negative effect of Al on growth performance.

Aluminum

Effect of dietary aluminum sulfate on calcium and phosphorus metabolism of broiler chicks.

The effect of dietary aluminum sulfate on Ca and P metabolism was studied using 1-day-old male broiler chicks. In Experiment 1, practical diets providing .90% Ca plus .45% available P (Pav), .90% Ca plus .78% Pav, 1.80% Ca plus .45% Pav, or 1.80% Ca plus .90% Pav were fed with 0 or .392% A1 as aluminum sulfate for 21 days. The control diet (.90% Ca plus .45% Pav) without added A1 was fed to all chicks during Days 22 to 49. In general, A1 significantly (P less than .05) decreased BW gain, feed intake, gain:feed ratio, plasma inorganic P (Pi), tibia breaking strength, tibia weight, percentage of tibia ash, and plasma Zn, measured at Day 21. Elevating Pav increased BW gain, feed intake, gain:feed ratio, tibia weight and plasma Zn, and decreased plasma total Ca in the presence of .392% A1 plus 1.80% Ca. Plasma Pi, tibia breaking strength, and percentage of tibia ash were increased by raising dietary Pav in the presence of .392% A1 with either level of Ca. Negative effects of dietary A1 on feed intake and BW persisted through Day 49. In Experiment 2, a control diet (.90% Ca, .45% Pav) was fed for ad libitum access either alone or supplemented with .2% A1 as aluminum sulfate or with an equivalent amount of sulfate provided by potassium sulfate. The control diet was also pair-fed to chicks given .2% A1. Dietary A1 significantly depressed weight gain, feed intake, gain:feed ratio, and plasma Pi.(ABSTRACT TRUNCATED AT 250 WORDS)

Alum Compounds

Effect of dietary aluminum on calcium and phosphorus metabolism and performance of laying hens.

The effect was studied of feeding dietary Al as aluminum sulfate on calcium and phosphorus metabolism and performance of Single Comb White Leghorn laying hens. In Trial 1, graded levels of Al (0, .05, .10, or .15%) were added to a corn-soybean meal layer diet containing 3.3% Ca and .5% available P. Each diet was fed for 28 days to six groups of six individually caged hens. Adding .15% Al to the diet significantly (P less than .05) reduced feed intake, egg production, body weight, tibia breaking strength, and plasma inorganic P. In Trial 2, graded levels of Al (0, .1, .2, or .3%) were added to the basal diet. Each diet was fed to five or six individually caged hens for 42 days. Feeding .3% Al significantly (P less than .05) decreased plasma inorganic P in samples collected immediately following oviposition after 10 and 42 days of treatment. Plasma total Ca, tibia weight, and tibia breaking strength were unaffected by dietary treatments. Egg production and feed intake during Days 1 through 21, but not during Days 22 through 42, were significantly reduced by .3% Al. The results indicated that the addition of .3% Al to a laying hen diet has a negative effect on P metabolism and egg production.

Aluminum

Adult respiratory distress syndrome: radiologic manifestations and course.

During a 36-month period, the serial chest x-ray films of 26 patients with the adult respiratory distress syndrome (ARDS) were evaluated for the patterns of onset, course, and follow-up appearance when possible. An exudative phase appearance can be recognized, which can clear. The exudative phase appearances are (1) a bilateral, homogeneous, white-out alveolar appearance; (2) an asymmetric consolidative appearance; and (3) a central perihilar ("bat-wing") consolidative appearance. This progresses to a proliferative phase manifested on chest x-ray film as an interstitial appearance that must not be confused with fibrosis, as the chest x-ray film may return to normal.

Adult

Changing patterns in pulmonary tuberculosis.

We reviewed the initial chest roentgenograms of 182 consecutive adult patients with proven active tuberculosis. Less than 50% of all cases were known or suspected at the time of initial presentation. There is a low degree of correlation between radiologically discernible active pulmonary tuberculosis and extrapulmonary tuberculosis. A high percentage of cases represent uncommon pulmonary locations. We present the frequency of occurrence of four common pulmonary patterns.

Adult

Effects of unidentified growth factor sources on feed preference of chicks.

The effect on feed preference of various feed ingredients considered to be sources of unidentified growth factors (UGF) was studied with egg-type chicks. In each experiment five or six pens of 20 males were assigned to each treatment. All chicks were fed a corn-soy basal diet with added fat during days 1 to 13. During days 14 to 21 chicks of the test treatment were offered a choice of the basal diet (Feeder 1) or a test diet with one of the UGF sources (Feeder 2). In pens of the control treatment both feeders contained the basal diet. All diets were approximately equal in calculated nutrient composition. The UGF sources, included at 5% of the diet, were meat and bone meal (MBM); fish solubles and meal (FSM); a commercial mixture made from fish, whey, and fermentation products (UGF mix); and distillers dried grains with solubles (DDGS). Each day feed consumption from each of the feeders was measured and their positions were alternated. Chicks showed a significant preference for FSM and UGF mix in two trials, no preference for MBM in one trial, and no preference for DDGS in one trial, and a significant rejection of DDGS in the other. No differences in weight gain were noted. The MBM decreased gain/feed and DDGS increased total feed intake in one of two trials. These studies indicate that some UGF sources improve feed preference in chicks fed practical diets.

Animals

Biological availability of selenodicysteine in chicks.

The biological availability of selenium (Se) in selenodicysteine (SDC) for chicks was evaluated using plasma glutathione peroxidase (SeGSHpx) activity and tissue Se levels as criteria. In each of two trials day-old Single Comb White Leghorn chicks were fed a basal diet low in Se but supplemented with vitamin E during Days 1 to 14. On Day 15 three replicate groups of eight chicks were assigned to each dietary treatment. Dietary treatments consisted of feeding the basal diet alone or supplemented with approximately 50, 100, or 150 ppb Se as either sodium selenite or SDC from Days 15 to 27. Pooled samples of blood, liver, and breast muscle were obtained from four chicks per replicate group on Day 27. Activity of SeGSHpx and the concentration of Se in plasma, whole blood, muscle, and liver were highly correlated (P less than .0001) with supplemental dietary Se. In Trial 1 no differences were observed between the slopes for each compound upon determining linear regression equations for SeGSHpx, plasma Se, whole blood Se, muscle Se, or liver Se versus supplemental dietary Se. In Trial 2 there were no differences between the slopes for each compound in equations for SeGSHpx, plasma Se, or whole blood Se versus supplemental dietary Se. The ratio of slopes (SDC/sodium selenite) was .82 for both muscle Se and liver Se versus dietary Se. Thus, data indicate that Se in SDC is highly available for chicks.

Animals

Radiologic considerations in the adult respiratory distress syndrome treated wih positive end expiratory pressure (PEEP).

Radiographic changes with ARDS are similar to alveolar pulmonary edema in the typical case, although early changes may also be nodular in a small number of cases. These may last about 4 days. Following early alveolar changes the later ARDS findings evolve into a diffuse interstitial pattern, and if the patient survives without complications, the chest x-ray may eventually clear completely. PEEP therapy may cause no x-ray changes or may manifest an apparent hyperinflation appearance to the chest x-ray. PEEP may result in barotrauma changes to the lungs manifested by vesicular rarefactions, lucent lines streaking toward the hilus, radiolucent halos around vessels, pneumatocele formation, and subpleural emphysema manifested by blebs or lucent lines on the chest x-ray. Barotrauma pulmonary changes preceded more serious complications such as pneumothorax, mediastinal emphysema and extrathoracic gas collection.

Adult

Improving hypertension control in a private medical practice.

Hypertension is one of the most common diseases seen by the practicing physician. Yet, because of noncompliance, conditions of many hypertensive patients are not effectively controlled by treatment. The purpose of this study was to test the efficacy of a patient education program in reducing the blood pressure (BP) of hypertensive patients in a private, solo medical practice. The intervention program focused on three behavioral objectives-pill taking, appointment keeping, and dietary sodium reduction while stressing the need for taking responsibility for one's own care. It was hypothesized that patients receiving an educational intervention stressing self-care would benefit more than those receiving the usual medical care. A substantial reduction in BP was considered to be the measure of successful treatment. Thirty-nine hypertensive patients receiving drug therapy from a private, solo medical practice were randomized into either a treatment group or a control group. A comparison of means disclosed no pretreatment differences between the groups' average BPs. After following up both groups for six months, mean changes in BP were compared for both treatment and control patients using a two-sample t test for independent samples. The BP fell in the treatment group (-13 mm Hg, systolic; -8 mm Hg, diastolic) but rose slightly in the control group (3 mm Hg, systolic 0.5 mm Hg, diastolic). The difference in changes was significant for both the systolic and diastolic BP.

Adult

Feed efficiency and gain responses to protein levels in two lines of birds selected for oxygen consumption.

Two experiments were conducted to investigate the response of two populations of chickens, divergently selected for high and low oxygen consumption, to varying protein levels. Protein levels used for Experiments 1 and 2 were 16, 18, 20, and 22% and 20, 22, 24, and 26%, respectively. The birds were weighed initially and weekly to 4 weeks of age. Feed consumption was ad libitum with amounts consumed recorded weekly. Gross feed efficiency was computed per pen as the difference between initial and weight at 4 weeks divided by feed consumed adjusted for spillage. The results from these experiments indicate that at low protein levels both lines were equally efficient, but, as the level of protein was increased, the low line was increasingly more efficient while the high line became less efficient. Gain for the low O2 birds was greater than the high O2 birds in all cases with both lines increasing in gains equally with increased protein levels.

Animal Feed

Pneumoperitoneum and pneumoretroperitoneum. Consequences of positive end-expiratory pressure therapy.

Patients receiving positive end-expiratory pressure (PEEP) therapy should be considered at risk for pneumoperitoneum. In the four patients described, chest roentgenographic demonstration of pulmonary interstitial gas and pneumomediastinum, frequently but not always associated with pneumothorax, preceded the dissection of gas into the abdominal cavity. Neither prompt intubation of the pleural space with reexpansion of the lung in the event of pneumothorax nor decrease in the PEEP applied precluded dissection of gas from the mediastinum into the retroperitoneal and peritoneal spaces. This sequence of roentgenographic events should strongly suggest pneumoretroperitoneum and pneumoperitoneum as a sequela to PEEP therapy rather than a ruptured viscus.

Adult

Pulmonary interstitial gas: first sign of barotrauma due to PEEP therapy.

Radiographic identification of pulmonary interstitial gas is a prime indicator of possible further complications in patients treated with PEEP therapy for severe respiratory failure. Records and chest radiographs of 89 adult patients treated with PEEP in a 40-month period were reviewed. Data of 7 were incomplete, 82 cases were analyzed. Of 17 patients who developed interstitial gas, 9 progressed to further barotrauma complications of pneumomediastinum, pneumothorax, and extrathoracic dissection. Interstitial gas is manifested radiographically by vesicular rarefactions (cystic changes), linear streaks along the bronchi and vessels, halos of gas around vessels, and subpleural gas.

Barotrauma

Acquired tracheomalacia: etiology and differential diagnosis.

The noninvasive diagnosis of impaired mechanical integrity or compliance of the trachea is most accurately made by fluoroscopic observation recorded on video tape or cineradiography, with or without benefit of artificial contrast media (contrast tracheography). In particular, localized buckling, collapse or dilatation indicative of focal tracheomalacia may thus be diagnosed in vivo and correlated with diseases of the central airways. Congenital tracheomalacia is a rare, bu, well described entity. Cases of acquired tracheomalacia occur with increasing frequency, but are often not clearly recognized. We contrast the dynamic behavior of the normal trachea with the abnormal dynamics characteristic of focal tracheomalacia. Such lesions may result from trauma, surgical procedures, chronic irritation, inflammation, mechanical changes, or malignancy.

Carcinoma, Adenoid Cystic

Relationship of heat tolerance and oxygen consumption in chickens.

Chicks from lines genetically selected for high or low heat tolerance were compared to lines selected for high or low oxygen consumption. Oxygen consumption, survival time, respiration rate, lung capacity and body weight were determined. Selection for high oxygen consumption ahd high heat tolerance resulted in birds with similar characteristics. The high line birds for both heat tolerance and oxygen consumption had greater oxygen consumption, survival time and lung capacity but lower body weight.

Animals