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Biomedical subjects

A C Johnson

Publications and source records attributed to A C Johnson.

At least 91 records · Page 5Linked to original sources
PubMed1987

Different mechanisms control developmental activation of transcription of genes subject to identical hormonal regulation in adult liver.

Developmental changes in expression of two genes subject to identical hormonal controls in adult liver were examined in livers of fetal and newborn rats. Both mRNA concentrations and transcription of tyrosine aminotransferase were very low throughout gestation and increased sharply at birth. The mRNA of gene 33 (Lee et al., J. Biol. Chem. 260: 16433-16438, 1985) and its transcription were also low in fetal liver until a significant increase occurred just prior to birth, followed by a further increase at birth. In mutant mice carrying a deletion that prevents developmental activation of aminotransferase transcription, that of gene 33 was not affected. The data indicate that different mechanisms control developmental activation of these genes, in contrast to hormonal regulation of their expression.

Aging↗
PubMed1986

Clostridial infection of renal cell carcinoma.

We report a case of a large gas-filled clostridial abscess in a previously unrecognized renal cell carcinoma. Neoplastic tissue has a nonhomogeneous blood supply, creating areas of hypoxia and reduced glucose concentrations, which lead to tumor necrosis and an environment conducive to the growth of anaerobic organisms. Anaerobic infection should be considered in any patient with carcinoma and fever. Conversely, abscess transformation of a tumor can be the explanation for what otherwise seems to be the spontaneous development of a parenchymal abscess.

Abscess↗
PubMed1985

Subcutaneous calcifications masquerading as pulmonary lesions in long-term hemodialysis. Review of nodular pulmonary opacities in the population undergoing hemodialysis.

Calcification of soft tissue frequently occurs in patients undergoing hemodialysis for chronic renal failure and involves the arteries, eyes, periarticular regions, lungs, heart, abdominal viscera, subcutaneous tissues, and skin. In this report, two such patients are described who presented with apparent pulmonary nodules on their chest roentgenograms obtained on admission. By the use of tomograms and apical lordotic views, both proved to have extrapulmonary calcific deposits in the subcutaneous tissues overlying the upper pulmonary zones. The tendency for these collections to undergo progression, regression, or pseudocavitation is illustrated. Definitive radiographic localization of lesions projecting over the pulmonary fields in patients undergoing hemodialysis is emphasized because of the significantly increased incidence of infection (including tuberculosis), septic embolism, and carcinoma.

Adult↗
PubMed1985

Intraluminal duodenal diverticulum.

A 46-year-old woman was seen for evaluation of dyspepsia of 8-wk duration. X-rays of the upper gastrointestinal tract revealed an intraluminally projecting diverticulum of the duodenal bulb. Diagnostic features and management of intraluminal duodenal diverticulum are reviewed.

Duodenal Obstruction↗
PubMed1984

Disseminated inoculation blastomycosis in a renal transplant recipient.

We report a case of inoculation blastomycosis with dissemination to the lungs. The patient, a renal allograft recipient, was inoculated accidentally at the veterinarian's office where she worked. A nodular lesion appeared at the inoculation site, accompanied by lymphadenopathy and fever. Pulmonary infiltrates developed. Blastomyces dermatitidis was identified by both biopsy and culture from both inoculation site and lungs. Although not previously reported, inoculation blastomycosis can disseminate in an immunocompromised patient.

Accidents, Occupational↗
PubMed1982

Cancer chemotherapy associated symptomatic stomatitis: role of Herpes simplex virus (HSV).

The relationship between oral shedding of Herpes simplex virus (HSV) and cytotoxic cancer chemotherapy was studied. HSV seropositive outpatients receiving cytotoxic chemotherapy had HSV recovered from throat washings in eight of 114 patients (7.0%), significantly more often than HSV seropositive outpatients with malignancy who were not receiving cytotoxic chemotherapy (one of 91 patients; 1.1%; P = 0.04). Twenty-eight HSV seropositive chemotherapy patients and 11 HSV seropositive healthy hospital personnel were studied serially 2-3 times per week over a 3-4 week period for oral HSV shedding. Although a comparable percentage of each group shed HSV at least once (57.1% of chemotherapy patients versus 36.4% of controls), chemotherapy patients had a strikingly higher incidence of multiple positive cultures: 40/218 attempts (18.7%) versus 4/156 attempts (2.6%) for controls (P less than 10(-5)). Among chemotherapy patients who developed clinically evident stomatitis, 12 of 14 (85.7%) had HSV recovered compared to four of 14 (28.6%) without lesions (P = 0.004). We conclude that while oral mucosal HSV infection is associated with symptomatic stomatitis following chemotherapy, HSV does not account for all mucosal lesions in chemotherapy patients.

Antibodies, Viral↗
PubMed1982

Tracheomegaly.

Explore the source record for details and available documents.

Aged↗
PubMed1981

Detection of experimentally produced acute pulmonary arterial occlusion by methyl iodide-131 inhalation imaging.

Methyl iodide-131 (CH3I-131) is described as an agent for detection of acute experimentally produced pulmonary arterial occlusion in dogs. When gaseous CH3I-131 is inhaled, radioactivity passes instantaneously from the alveoli to the lung capillary bed. Where pulmonary blood flow exists, activity is washed out into the systemic circulation, but in areas of blood stasis, a transient pulmonary "hot spot" remains. CH3I-131 is easily produced and inexpensive, but administration is awkward and strict radiation safety precautions are mandatory.

Animals↗