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Biomedical subjects

J C Alexander

Publications and source records attributed to J C Alexander.

At least 55 records · Page 3Linked to original sources
PubMed1980

Lung abscess and empyema of the thorax.

Empyema is best managed by the physician familiar with the indications and principals of the various procedures used in the treatment of empyema of the thorax. The objective of each modality used to treat empyema is to drain the pleura cavity and to allow full expansion of the lung. If the infected material can be removed and the visceral and parietal pleural approximated, the body will heal the pleural infection. The procedure chosen to treat empyema greatly depends upon the phase of maturation of the empyema when treatment is begun.

Adult↗
PubMed1979

Fatty acid composition of heart cells exposed to thermally oxidized fats.

Corn oil and olive oil were thermally oxidized, and the free fatty acids from the fresh fats, and from the distillable non-urea-adductable (DNUA) fractions of the thermally oxidized fats were prepared. These were added as emulsions to the medium of primary cultures of heart endothelial and muscle cells from neonatal rats. After exposure for 24 hr, the fatty acid composition of the triacylglycerol (TC) and phospholipid (PL) fractions of the cells was determined. Reflecting the nature of the fat used, the corn oil treatment produced relatively higher concentrations of linoleic acid in the TG and PL fractions compared to the olive oil treatment, in which case the oleic acid level was influenced. Treatment of the cultured cells with components derived from oxidized corn oil or oxidized olive oil resulted in lower concentrations of linoleic an arachidonic acids in the PL moieties compared to the fresh fat controls. However, there were marked increases in arachidonic acid in the TG fractions of both the endothelial and muscle cells. These changes due to the DNUA from thermally oxidized fats indicate a distinct metabolic response to the derivatives formed during thermal oxidation of the fats.

Animals↗
PubMed1979

Effects of prolonged cyanide and thiocyanate feeding in rats.

Male weaning rats were fed a semipurified diet containing 10% casein; this diet restricted in methionine, vitamin B12, and iodine; or the complete and restricted diets supplemented with either 1500 ppm potassium cyanide or 2240 ppm potassium thiocyanate for 11.5 mo. There were no deaths or clinical signs of toxicity. Cyanide, but not thiocyanate, caused a consistent reduction in weight gain in the complete and restricted groups. Both cyanide and thiocyanate caused decreased thyroid gland activity in young rats, particularly in the restricted groups. Plasma thyroxine concentrations were maintained in the mature cyanide-treated rats, even though secretion rates were decreased. However, the mature thiocyanate-treated animals showed decreased plasma thyroxine concentrations, despite thyroid gland enlargement. Modest primary myelin degeneration in the spinal cord white matter was found in the restricted group and in rats receiving this diet supplemented with either cyanide or thiocyanate. The lesions did not resemble those of a vitamin B12 deficiency in appearance or those of acute cyanide intoxication in distribution. Because of tissue autolysis, it could not be determined whether these changes resulted from histotoxic anoxia or an alteration of oligodendroglial myelin metabolism.

Animals↗
PubMed1979

Subchronic toxicity test for two thermotolerant filamentous fungi used for single cell protein production.

Safety evaluations of two thermotolerant filamentous fungi, Cephalosporium eichhorniae 152 (C. 152) and Rhizopus chinensis 180 (R. 180), grown on a sugar-salts medium were carried out through feeding the biomases to rats at 20% or 40% dietary levels for 90 days. There was a control group fed soybean meal. Weight gain and feed consumption for rats fed 20% C. 152 were equal to those for the control animals, but were depressed in the other three groups, especially the rats fed R. 180. All animals appeared normal and healthy except that transient alopecia was found for a short duration in the fungi-treated rats in the initial period. The cause of this lesion is not clear. At the end of the feeding trial, clinical determinations of constituents in blood and urine samples were conducted. The animals were autopsied and weights for four organs were taken. Histopathological examinations for 26 different tissues were carried out. Mild changes were found in both C. 152 and R. 180-treated rats but most of the these were not considered to be related to treatment.

Acremonium↗
PubMed1978

CEA levels in patients with carcinoma of the esophagus.

Serum CEA levels were determined serially by the Hansen Z gel technique on 41 patients with carcinoma of the esophagus and compared to 276 controls. Seventy percent of patients with carcinomas of the esophagus had elevated CEA levels. CEA levels greater than 10.0 ng/ml after therapy correlated with significantly shortened survival. CEA appears promising as an indicator of tumor presence in patients with carcinoma of the esophagus.

Adult↗
PubMed1978

Nutritional and metabolic studies of distillable fractions from fresh and thermally oxidized corn oil and olive oil.

A semisynthetic diet containing 15% by weight of dietary fat was fed to six groups of male wistar rats for 28 days. Two groups received the distillable fraction of fresh corn oil (DCO) or fresh olive oil (DOO), two groups the distallable fractions of the thermally oxidized fats (OCO,OOO), and two groups received the respective fresh fats as controls (FCO, FOO). Substantial changes in the fatty acid composition occurred in the fats upon thermal oxidation. Only the rats that received OOO showed overt symptoms of heated fat toxicity. This was reflected in the histological scores of these animals with the liver sustaining the most numerous and severe lesions. Tissue fatty acid changes of any significance were confined largely to the polar liver lipid of the rats that were fed OCO or OOO. The results of this study would suggest that the relatively greater toxicity of OOO, compared to OCO, may in part be due to the high oleic:linoleic acid ratio of the fresh olive oil and in part to a higher tocopherol content of the corn oil.

Adipose Tissue↗
PubMed1978

Uptake and utilization of 1-14C palmitic acid by heart cells treated with fresh or thermally oxidized fats.

The effects of fractions isolated from thermally oxidized corn oil or olive oil on the metabolic activity of heart endothelial and muscle cells were studied. Rat heart cells in culture, exposed to thermally oxidized fat components, took up more exogenous 1-14C-palmitic acid and incorporated more of it into the cell triacylglycerol fraction than when the cells were treated with fresh fats. Particularly with the heated corn oil compared to fresh corn oil, much less of the radioactivity from the labeled palmitic acid was deposited in the phospholipid fraction. Also, with heated corn oil when the incubation period was extended beyond 12 hr, there was a decline in the radioactivity retained in the triacylglycerol fraction of the heart muscle cells. When the fresh fats were compared for 14C-radioactivity incorporation into the heart cells, the olive oil gave much higher values, indicating a distinct difference in response to the proportion of fatty acids supplied.

Animals↗
PubMed1978

Utilization of 35S from radioactive methionine or sulfate in the detoxification of cyanide by rats.

Weanling rats were fed a semipurified diet based on 10% casein and 1,500 ppm potassium cyanide. The diet was supplemented with varying levels of DL-methionine and/or potassium sulfate such that all diets were iso-sulfurous except for the basal which had no additional sulfur. The animals were fed for 2 weeks after which half of the rats in all groups except the basal were used in a radioactive study. Urine was collected and analyzed for thiocyanate. Animals which received labeled methionine were more efficient in producing labeled thiocyanate than those which received labeled sodium sulfate, although the latter did contribute to the detoxification of cyanide. Increases due to additional methionine were larger for weight gain, feed consumption, and urinary and plasma thiocyanate than with supplemental sulfate.

Animals↗
PubMed1977

Effect of thymosin in vitro on T cell levels during radiation therapy: correlations with radiation portal and initial T cell levels.

The effect of thymosin in vitro on percent T cells was determined in 388 blood specimens from patients with head and neck, mediastinal, and pelvic malignancies during radiation therapy, in 94 untreated patients with these malignancies, and 277 normal adults. Changes in percent T cell levels after incubation of lymphocytes with thymosin did not correlate with tumor histology or cumulative radiation dose, but in all groups correlated with radiation portal and initial T cell levels. T cell levels increased by a similar increment in normals and in the untreated patients. During irradiation, the mean levels after incubation with thymosin did not change in patients with head and neck and pelvic malignancies, but in patients with mediastinal malignancies the levels increased significantly more than in normals. For a given T cell level, the increase in patients with mediastinal malignancies was greater than in patients with pelvic malignancies, and as a group was greater than in patients with head and neck malignancies. The results can be explained by an increase in circulating thymosin-responsive lymphocytes during mediastinal irradiation due to suppression of a function of the thymus important for maturation of these cells, and a decrease in these cells during pelvic irradiation due to a deleterious effect on precursors in pelvic bone marrow. The results thus provide a rationale for clinical trials to assess the efficacy of thymosin in averting declines of T cell levels in patients receiving mediastinal irradiation.

Adolescent↗
PubMed1977

Correlations among serum protein-bound carbohydrates, serum glycoproteins, lymphocyte reactivity, and tumors burden in cancer patients.

Levels of glycoprotein-associated carbohydrates (neutral hexoses, hexosamine, sialic acid and fucose) were determined in the serum of patients with either local, regional or metastatic cancer, patients clinically cured of cancer, and controls (smokers and nonsmokers). Total protein-bound carbohydrates were compared with levels of 17 normal serum glycoproteins, carcinoembryonic antigen (CEA), and with lymphocyte reactivity to phytohemagglutin (PHA). Tumor burden was directly related to protein-bound carbohydrate levels in patient groups. Levels of bound carbohydrates reflect the sum of all the changes in serum glycoproteins, but primarily changes in the acute-phase proteins (alpha 1-acid glycoprotein, alpha 1-antitrypsin, haptoglobin, ceruloplasmin) found in the alpha-globulin fraction of serum. Increases in protein-bound carbohydrates in tumor-bearers were not related to increases in CEA. Increased levels of the acute-phase proteins occurred in individuals with depressed in vitro lymphocyte reactivity to PHA. A significant positive correlation was found between lymphocyte reactivity and level of alpha 2HS-glycoprotein. The results suggest that serum protein-bound carbohydrates or glycoproteins may be of adjunctive value is assessing tumor burden and immune reactivity in cancer patients.

Carbohydrates↗
PubMed1977

Fate of orally dosed linamarin in the rat.

Wistar rats, about 100 g in weight, were dosed by stomach tube with 30 mg of pure linamarin. No intact linamarin was identified in the feces or blood but 5.65 mg was excreted in the urine along with 0.823 mg of thiocyanate ion. A 50-mg dose of linamarin was lethal to 7 of 10 rats receiving this dose.

Administration, Oral↗
PubMed1977

Safety evaluation of Aspergillus fumigatus grown on cassava for use as an animal feed.

A safety evaluation of Aspergillus fumigatus I21, grown in a cassava carbohydrate and salts medium, was undertaken. Male weanling rats were fed the fungus at 20, 30 and 40% of the diet for 90 days. A control group was given soybean oil meal as the sole source of protein. Weekly determinations of the body weights and feed consumptions were made. A few days prior to termination of the feeding study, a kidney function test was undertaken on the rats. At the end of the feeding period hematology, blood biochemistry, urine analyses and histopathology studies of various tissues were carried out, and organs were weighed. Rats fed A. fumigatus I21 gained less weight than the controls, but kidney weights were increased. Increases in serum alkaline phosphatase and glutamic-oxaloacetic transaminase were not related to dose level. The blood urea nitrogen was increased for the rats fed 40% of the fungus. Rats fed 30 and 40% of the fungus I21 showed a significant drop in albumin. Deficiency in methionine or other essential amino acids through a limited feed consumption may have caused a decrease in albumin synthesis. Rats fed the highest level of the fungus showed increases in neutrophils and monocytes concomitant with decreases in lymphocytes and eosinophils which may be a response to stress. The urine analyses did not reveal any significant differences. The test rats were capable of concentrating urine adequately when deprived of water for 24 hours. No significant differences between the control and experimental groups were found by histopathological examinations.

Animal Feed↗
PubMed1977

Biochemical and histological effects of feeding thermally oxidized rapeseed oil and lard to rats.

Four groups of weanling rats were fed semisynthetic diets containing 15 percent by weight of dietary fats for 28 days. Two groups received thermally oxidized low-erucic acid rapeseed oil (OLE) or lard (OLA) and the other two groups received the respective fresh fats (FLE, FLA) as controls. Average daily feed consumption and feed efficiency were not affected by either OLE or OLA, however final body weights were depressed by the OLA in the diet. The relative heart weights and heart total lipids were significantly increased in both the OLE and OLA groups. A majority of the animals in both the OLE and OLA groups exhibited various gross symptoms attributable to heated fat toxicity such as seborrhea, diarrhea and polyuria. Excessive hair loss was noted in all the animals fed the heated fats. Tissue fatty acid changes due to OLA were confined largely to the polar liver lipids, whereas OLE produced dramatic changes in both the neutral heart lipids as well as in the neutral and polar liver lipids. Histological evaluation of the hearts, livers and kidneys indicated that OLA was very injurious to the kidneys, whereas OLE caused greater damage to both the hearts and livers.

Animals↗
PubMed1976

Effect of age and cigarette smoking on carcinoembryonic antigen levels.

Serum carcinoembryonic antigen (CEA) levels were determined by the Hansen-Z-gel technique in 276 healthy volunteers, of whom 154 were smokers and 122 nonsmokers. The mean CEA level was significantly higher in smokers (2.7 ng/ml) than in nonsmokers (1.9 ng/ml) (P less than .001), and a significantly higher percentage of smokers had elevated CEA levels (P less than .05). In both groups, CEA levels were directly related to age. Seventy-six of the 154 smokers who entered the study ceased smoking. Their CEA levels were determined at one, three, and six months after cessation of smoking. Within three months after cessation, elevated CEA levels declined to within the range of nonsmokers and did not appear to be influenced by previous smoking habits. Both age and smoking history must be considered for accurate evaluation of CEA levels. A reappraisal of the diseases associated with elevated CEA levels that considers the influence of age and smoking may invalidate some of the correlations previously reported.

Adolescent↗