Effect of carbon monoxide inhalation exposure in mice on drug metabolism in vivo

Experiments were undertaken to evaluate the action of carbon monoxide (CO) on the mixed-function oxidase (MFO) system in vivo. Mice were exposed to 500 ppm CO for 8 h per day in an inhalation chamber under dynamic airflow conditions. Hexobarbital (150 mg/kg, i.p.), zoxazolamine (150 mg/kg, i.p.) or ethanol (2 mg/g, i.p.) was given to each group of mice during CO exposure and disappearance of the drug from blood or brain was determined while CO exposure continued. The experiments were repeated with different groups of animals which were exposed to CO for 3 or 5 days. Hexobarbital and ethanol metabolism were not affected by CO following either one day exposure or repeated exposure. There was no statistically significant difference in the brain level of zoxazolamine in animals exposed to CO when compared to control. These studies indicate that in vivo metabolism of hexobarbital, zoxazolamine and ethanol in mice is not affected by exposure to 500 ppm CO under the conditions employed in the present study.

Longitudinal chest x-ray changes in normal men

To determine the changes on chest x-ray attributable to the aging process, we evaluated cardiovascular and pulmonary structures on two standard postero-anterior chest x-rays taken at least 10 years apart (M = 16.9 years) in 67 carefully screened healthy men initially aged 23 to 76 years. The aortic knob diameter increased in 79% of subjects. Although mean cardiothoracic ratio increased overall, only 3% of men developed a cardiothoracic ratio greater than .50, and none exceeded .51. Pulmonary abnormalities on initial chest x-ray consisted mainly of hyperinflation (27%) and increased markings (19%), both of which doubled in prevalence during follow-up. Kerley B lines and enlarged pulmonary arteries were rare initially but increased three- to five-fold. The prevalence of these findings did not differ between smokers and nonsmokers. Based on commonly accepted x-ray criteria, chronic obstructive lung disease was suggested in 15% of the initial films and 21% of the final films despite the absence of clinical or spirometric abnormalities.

Starvation stimulates pancreatic PGE content

Recent evidence suggests that prostaglandins may exert a tonic inhibitory tone in the pancreatic beta cell during starvation. The effects of starvation on rat pancreatic prostaglandin E (PGE) content were studied. After 72 hrs of starvation, pancreatic PGE increased 250% above that of fed controls. Administration of streptozotocin, a selective beta-cell toxin, decreased pancreatic PGE significantly (p less than 0.005), but starvation partially reversed this trend. Thus, PGE may have a physiological role in modulating insulin secretion during starvation. It appears that both beta-cell and nonbeta-cell sources of PGE are involved in this phenomenon.

Sciatin: immunocytochemical localization of a myotrophic protein in chicken neural tissues

A mytotrophic protein (sciatin) purified from chicken sciatic nerves has "trophic" or "maintenance" effects on cultured muscle. We have elicited a specific antiserum against purified sciatin in rabbits. Using this antiserum, we investigated the distribution of sciatin in embryonic and adult chicken tissues by an unlabeled peroxidase-an-tiperoxidase method at the light microscopic level. The antiserum stained adult chicken neural tissues in situ and cultured embryonic chick neurons. Staining was intense in the cell bodies of spinal cord neurons and the axoplasm of sciatic nerves. These was reaction product seen in the outer margins of myelin sheaths that corresponded to the Schwann cell cytoplasm. Cerebral cortical neurons were weakly stained by the antiserum. No staining was apparent in oligodendrocytes or astrocytes. Nonneural tissues, such as skeletal, smooth and cardiac muscle, kidney, and liver, were also unstained by the antiserum. Cultured spinal cord neurons, cerebral cortical neurons, and sensory neurons were stained immunocytochemically by the antiserum. There was no reaction product seen in the glial cells that are usually present in neuronal cultures or cultured cells from liver, kidney, skeletal muscle, smooth muscle, and cardiac muscle. Our results thus show that the myotrophic protein is localized in neuronal perikarya and their processes in vivo as well as in vitro.

Effect of sodium oleate on plasma secretin concentration and pancreatic secretion in dog

The effects of sodium oleate and triglyceride infused into the duodenum of dogs with chronic pancreatic fistulas on pancreatic secretion and plasma immunoreactive secretin were investigated. The responses were compared with those following intravenous secretin infusions. Oleate markedly increased pancreatic water and bicarbonate secretion in a dose-related fashion, and these increases were accompanied by a small, but significant rise in the level of circulating immunoreactive secretin. No change in pancreatic secretion or in plasma secretin level was observed by the administration of triglyceride. Comparison of the bicarbonate response after oleate infusion with that after secretin administration suggests that the pancreatic stimulatory effect of intraduodenal sodium oleate is mediated to a major extent by the release of endogenous secretin.

Role of secretin on postprandial gastrin release in the dog: a further study

To determine the physiologic role of secretin on gastric secretory function, the effects of secretin in a physiologic dose on gastrin release and gastric acid secretion were studied in four dogs with vagally innervated fundic pouches. Three sets of experiments were performed in each dog: (1) meal alone, (2) meal after intravenous cimetidine to suppress acid secretion and release of secretin, and (3) meal after intravenous cimetidine with simultaneous intravenous secretin, 0.03 clinical unit (CU)/kg-hr. A significant increase in plasma secretin concentration occurred after ingestion of a meal. The postprandial increase in the secretin level was abolished by intravenous cimetidine 200 mg, whereas intravenous cimetidine resulted in a marked increase in the postprandial plasma gastrin concentration which was significantly greater than that after a meal alone. A plasma secretin level comparable to that of the postprandial period could be achieved in the same fasting dogs by intravenous secretin, 0.03 U/kg-hr in 2% dog albumin solution. The postprandial plasma gastrin concentration and acid secretion following intravenous cimetidine were significantly decreased by simultaneous intravenous secretin at a dose of 0.03 U/kg-hr. The observations indicate that secretin plays a significant role in the regulation of release of gastrin and gastric secretion of acid in the postprandial state in dogs.

Subdural metastases from prostatic adenocarcinoma

Adenocarcinoma of the prostate commonly metastasizes to lymph nodes and bones, with occasional visceral deposits; lesions in the brain are rare. Although leptomeningeal carcinomatosis secondary to prostatic tumor has been reported, discrete cranial dural metastases from prostatic adenocarcinoma have not been described previously. The case of a patient having a unique adenocarcinoma of the prostate with bone, lymph node, and subdural metastatic lesions is presented.

24-Hour plasma secretin level and pancreatic secretion in dog

Plasma secretin concentrations were determined and duodenal pH was recorded continuously for a period of 24 hours after ingestion of a meal in 3 dogs with gastric cannula and duodenal cannula and in 4 dogs with pancratic fistulae. The mean plasma secretin concentration increased significantly after a meal and it remained elevated for the first 12-hour period (peak at 30 min). Duodenal pH frequently decreased below 4.5 during the first 12-hour postprandial period, but it remained above 5.0 during the second 12 hours. Pancreatic secretion peaked during the first hour of meal ingestion and remained elevated until the end of 12 hours. The increased plasma secretin level in pancreatic fistula dog during the postprandial period was significantly greater than that of duodenal cannula dog, but the trends of increase in the secretin levels were quite identical. The present study indicates that: (1) plasma secretin concentration increases significantly within 30 min after a meal and remains increased during the first 12-hour period, (2) duodenal pH frequently decreaded below 4.5 during the same 12 hours but more frequently during the first 6 hours, and (3) a significant increase in pancreatic water, HC03- and protein occurred during the same time period.

Scintiscans and computer assisted tomographic findings of herpesencephalitis

The radionuclide, CAT and angiographic features of a case of herpes simplex encephalitis are present. A dramatic change in the abnormal perfusion and static concentration of tracer activity resulted following chemotherapy with Adenine arabinoside. The improvement seen on the dynamic and static scintiscans correlates closely with the patient's clinical course and CAT findings. The radionuclide perfusion study is of particular importance in documenting the diminished activity of the inflammatory process following therapy.

Clinical significance of 99mtechnetium sulfur colloid accumulation in renal transplant patients

The accumulation of 99mtechnetium sulfur colloid (99mTcSC) was evaluated in 47 studies performed on 19 renal transplant patients by comparing its transplant activity to its bone marrow accumulation. There was a diagnosis of rejection of 21 of 22 studies (96.5%) in which marked transplant accumulation was noted. In 11 studies of patients with a clinical diagnosis of post-transplant acute tubular necrosis (ATN), the transplant activity varied from none to moderate. Rejection developed in 5 of 6 studies with minimal to moderate accumulation. Normally functioning renal transplant patients, or those with ATN and no superimposed rejection, do not show evidence of 99mTcSC accumulation.

Radiography and scintigraphy in tumoral calcinosis

A case of tumoral calcinosis with tumoral deposits about the knee is reported. Radiographs demonstrate juxta-articular calcific deposits about the right second and fifth distal interphalangeal joints and the left first distal tuft, both hips, both shoulders, first distal phalanx of the left foot and right knee. Radionuclide images clearly demonstrate all areas of tumoral calcinosis.

Scintigraphic patterns of gallium-67 uptake in the breast

A review of 542 67Ga scans was undertaken to determine the incidence of 67Ga uptake in the "normal" breast, to establish factors modifying the uptke of 67Ga, and to define patterns of "normal" vs. pathologic accumulation. Nonpathologic uptake of 67Ga was demonstrated in 29 patients (12% of female patients) and was most often associated with conditions stimulating prolactin production or related to estrogenic hormone administration. This type of uptake was symmetrical but of varying pattern depending on the underlying stimulus. Pathologic uptake of 67Ga was demonstrated in 3 cases and always resulted in asymmetrical appearance of the breasts.

Nature of interaction of dextran sulfate with lecithin dispersions and lysolecithin micelles

Lecithin and lecithin/cholesterol dispersions as well as lysolecithin micelles were used to provide basic information on the mechanism of the interaction of zwitterionic phospholipids with dextran sulfate. The addition of dextran sulfate to lecithin dispersions or lysolecithin micelles in the presence of Ca2+ produced insoluble complexes. At each Ca2+ concentration, the amount of insoluble complex formed was maximal at the equivalence dextran sulfate/phospholipid weight ratio. An increase in CaCl2 concentration up to 10 mM progressively increased the equivalence ratios for the phospholipids. Further increase in Ca2+ concentration did not influence the equivalence ratio for maximal complex formation. The conversion of lecithin dispersions into insoluble complexes was very effective even at low Ca2+ concentrations. Approximately 70% of the lecithin was converted to the insoluble complex at CaCl2 concentrations as low as 0.5 mM and the complete conversion was observed at CaCl2 concentrations above 2.5 mM. In the presence of cholesterol, the precipitation curve for insoluble complex formation became broader than that of lecithin alone, indicating the enhancing effect of cholesterol on the insoluble complex formation both below and above the equivalence ratio. The stoichiometry of the interaction of the zwitterionic phospholipids with dextran sulfate inthe presence of calcium was determined using lysolecithin micelles. At the CaCl2 concentrations above 20 mM, the insoluble complex possessed a ratio of lysolecithin/calcium/sulfate group of approximately 2/1/3 (mol/mol/mol). It appears that the formation of the insoluble complex of lecithin or lysolecithin with dextran sulfate represents the mutually enhancing interactions involving both positive and negative charges of the zwitterionic phospholipids. These are the direct electro static interaction between the phospholipid choline nitrogen and the sulfate groups of dextran sulfate and the calcium cross-linking of the phosphate groups to the sulfate groups or to the phosphate groups of neighboring phospholipids.