Biomedical subjects

C I Hood

Publications and source records attributed to C I Hood.

At least 37 records · Page 2Linked to original sources

PubMed1981

Tracheal mucosal damage after aspiration. A scanning electron Microscope study.

Aspiration of gastric contents causes severe pneumonitis, but the effects of such aspiration on the large airways have not been well studied. To evaluate the effects of gastric contents on the tracheal mucosa, 63 healthy A/J mice were anesthetized and aspirated either sterile saline (pH, 5.9) (Group I), hydrochloric acid (pH, 1.5) (Group II), canine gastric juice (pH, 1.5) (Group III), or canine gastric juice (pH, 5.9) (Group IV). Tracer studies showed that the average amount aspirated was 15% of the administered dose. Animals from each group were killed by cervical dislocation at 1, 6, 24, 48, and 72 h and 7 days after aspiration. Examination of the tracheas by scanning electron microscopy revealed normal mucosa in all Group I animals. Tracheas from Group II animals killed between 6 and 48 h after aspiration showed desquamation of the superficial cell layer with complete loss of ciliated and nonciliated cells. Regeneration was noted at 3 days with complete recovery by 7 days. Tracheas from Group III animals had similar changes but regeneration was delayed, whereas those from Group IV had mild desquamation with delayed regeneration. The lungs of group I animals were normal, and those of animals in Group II through IV showed only small widely separated areas of inflammation. We conclude that (1) gastric contents cause marked damage to the tracheal mucosa even when the amount aspirated is too small to induce a clinically significant pneumonia, (2) damage is more severe when the pH of the gastric content is low, and (3) gastric juice may contain substances that delay healing.

Animals↗

PubMed1980

The EOG and choroidal malignant melanomas.

Fifty-four patients with a unilateral pigmented choroidal lesion were studied with electrooculography (EOG). Eighteen of 21 patients with histologically proven (13) or presumed (8) malignant tumors of the choroid had light peak-dark trough ratios (L/D) less than or equal to 150. Seventeen of 21 patients in the malignant group had an interocular L/D difference (L/Dd) greater than or equal to 23%, whereas only one of 33 patients with nevi or a condition simulating a nevus had a percent difference of such magnitude. Combining the L/D and L/Dd criteria resulted in a 98% accurate double-blind prediction of the final clinical/pathological results. The EOG is an objective, noninvasive test useful in the diagnosis of choroidal malignant melanomas.

Adolescent↗

PubMed1980

The pulmonary consequences of aspiration of gastric contents at pH values greater than 2.5.

Physiologic and pathologic responses of dogs were studied to assess the effect on the lungs of aspiration of gastric contents at a pH value greater than 2.5. Experimental solutions were administered into the lungs at a dose of 2 ml/kg. Animals were divided into 5 groups: group 1 (n = 13) received saline at a pH of 5.9; group 2 (n = 8) received hydrochloric acid (HCl) at a pH of 1.8; group 3 (n = 6) received gastric contents containing small food particles at a pH of 5.9; group 4 (n = 6) received gastric contents containing food particles at a pH of 1.8; group 5 (n = 6) received gastric contents at a pH of 5.9 from which food particles had been filtered. Arterial blood gas tension, fractional intrapulmonary shunt, and blood pressure were measured at intervals for 48 h. Animals that received gastric contents at a pH of 5.9 and severe hypoxia and increased intrapulmonary shunting that were significantly greater than those of animals receiving saline and were as severe as those of animals receiving HCl at a pH of 1.8. If food particles were in the aspirate, hypercapnia and acidosis were noted. There was pneumonitis in lung sections taken from animals in groups 2, 3, and 4, but not groups 1 and 5. These findings contradict the common belief that aspiration of gastric contents at a pH greater than 2.5 is benign.

Animals↗

PubMed1980

Nodular pulmonary amyloidosis. Description of a case with ultrastructure.

A 64-year-old man with a suspicious asymptomatic coin lesion received a thoracotomy that showed two foci of isolated nodular pulmonary amyloidosis. Ultrastructural analysis verified the amyloid nature of the lesion and suggested that the fibrils were produced by plasma cells and processed by macrophages. The pathogenesis of this lesion is discussed in light of recent studies.

Amyloidosis↗

PubMed1977

Epithelial downgrowth following penetrating keratoplasty in the aphake.

Four of approximately 1,500 patients receiving corneal grafts developed epithelial downgrowth following penetrating keratoplasty. All were aphakic prior to grafting and had complicated postoperative courses. Epithelial proliferation over the iris and endothelium was demonstrated in three cases at the time of a repeat keratoplasty. While rare, this complication may occur more frequently than has been previously recognized.

Aged↗

PubMed1977

Fungus implantation with wooden intraocular foreign bodies.

Four cases of wooden intraocular foreign bodies are presented. In each case the foreign body was found to be contaminated by fungi which may have contributed to the intraocular inflammatory response but did not actively invade ocular tissues. Tolerance of the eyes to the retained wooden material was very poor.

Adult↗

PubMed1976

Liquid ventilation of primates.

Three adult monkeys were anesthetized with ketamine and ventilated with fluorocarbon liquid [perfluoro bis (1, 4-isopropoxy) butane (Caroxin-D)] at 1 atmosphere on two separate occasions. During five runs, liquid ventilation was continued for 60 minutes. The sixth run was continued for ten minutes. Arterial blood gas levels during and after liquid ventilation were adequate for survival. Three years after the first period of liquid ventilation, the animals were killed. Approximately 0.001 mg of fluorocarbon per gram of tissue was present in the kidney, liver, brain, spleen, muscle, and heart. Fat contained approximately seven to nine times this amount, and the lung and pulmonary lymph nodes contained approximately 1,000 times this amount. In no case was it clinically evident that the monkeys had undergone periods of liquid ventilation. We conclude that primates can be ventilated successfully with liquid fluorocarbon on at least two separate occasions and can return to breathing air without obvious deleterious effects, but fluorocarbon is retained in small amounts for at least three years.

Adipose Tissue↗

PubMed1975

Residual levels and biochemical changes after ventilation with perfluorinated liquid.

Twenty-three beagle dogs were ventilated with perfluorinated liquid, perfluoro-1-isopropoxy-hexane (Caroxin-F) for 1 h and were reconverted to gaseous breathing. Hematologic and biochemical changes were studied in five dogs for 1 yr and the remaining animals were followed for evidence of retained Caroxin-F for up to 3 yr. We found that the dogs could be ventilated with liquid Caroxin-F and returned to spontaneous breathing of gaseous oxygen with normal blood gas exchange within 24-72 h. Serum alkaline phosphatase, serum cholesterol, and white blood cell count increased with liquid ventilation but returned to normal in less than 1 wk. Trace amounts of Caroxin-F were detected by chromatography in all tissues studied for the entire 3-yr period. The highest levels of Caroxin-F were found in the lungs and associated lymph nodes. No histologic evidence of the presence of Caroxin-F was seen except for local accumulations of vacuolated macrophages in the lungs and associated lymph nodes. We conclude that Caroxin-F can be breathed without residual deleterious effects, even though trace amounts remained for at least 3 yr.

Alkaline Phosphatase↗

PubMed1975

Long-term results of continuous oxygen therapy at sea level.

Twelve patients with hypoxemia associated with severe chronic obstructive pulmonary disease were treated with continuous portable oxygen therapy and have been followed up for a mean period of 25.2 months at sea level. Pulmonary function testing has revealed no further significant deterioration at long-term follow-up (17 months). After oxygen therapy was initiated, arterial carbon dioxide tension increased slightly, but decreased to pretreatment levels when patients were allowed to breathe room air. The electrocardiogram, which was unchanged at one month, has shown some reversal of cor pulmonale in five patients. Six patients have died, yielding a 56 percent survival rate at two-and-one-half years by the life table analysis. Five patients were autopsied, with possible oxygen toxicity being present in only one. The quality of life in our patients was improved and was especially represented by a reduction in hospital admissions for respiratory illness. We believe that continuous oxygen therapy is beneficial and worthwhile economically in certain patients.

Altitude↗

PubMed1974