The Esophageal Propulsive Force: Esophageal Response to Acute Obstruction

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Abstract

The response of the normal human esophagus to an obstructing intraluminal bolus was investigated and compared to the response evoked by transient intraluminal distention. A balloon, immobilized within the esophagus by external attachment to a force transducer, was inflated with from 3 to 25 ml of air for from 3 to 210 sec. Pressure phenomena occurring in the esophagus were simultaneously recorded from the body of the esophagus above and below the balloon.

Authors

Daniel H. Winship, F. Frank Zboralske

Regional Myocardial Blood Flow

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Abstract

A method is described which measures the local effectiveness of the myocardial circulation, expressed as a clearance constant. Uniform clearance constants have been demonstrated in the normal canine and human myocardium. A distinct difference in clearance constants has been demonstrated between the normal canine myocardium and areas of naturally occurring disease. Heterogeneous clearance constants have been found in a majority of human subjects with coronary artery disease—the lowest rates being noted in areas of fibrous aneurysm.

Authors

Jay M. Sullivan, Warren J. Taylor, William C. Elliott, Richard Gorlin

Comparative Effects of Insulin on Adipose Tissue Segments and Isolated Fat Cells of Rat and Man

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Abstract

In vitro metabolism of glucose-1-14C by adipose tissue into 14CO2 and total 14C lipids in rat and man was compared employing both adipose tissue segments and isolated fat cells prepared from the same donor. In the rat, the basal glucose metabolism and response to insulin decreased with increasing body weight for both adipose tissue segments and isolated cells. Regardless of age, the isolated cells exhibited a persistently higher metabolic activity. Of the parameters selected, conversion to CO2 was more pronounced than that to lipid.

Authors

F. Arnold Gries, Jürgen Steinke

Studies of the Metabolic Activity of Leukocytes from Patients with a Genetic Abnormality of Phagocytic Function

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Abstract

Polymorphonuclear leukocytes from patients with chronic granulomatous disease respond to the phagocytosis of latex particles with normal increments in glucose consumption, lactate production, Krebs' cycle activity, and lipid turnover.

Authors

Beulah Holmes, Arthur R. Page, Robert A. Good

Competitive Effects of Some Cations on Active Potassium Transport in the Human Red Blood Cell

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Abstract

The effect of some cations on the active potassium transport system of the human red blood cell has been investigated. At low extracellular potassium concentrations, extracellular sodium competitively inhibits the active potassium influx at all sodium concentrations investigated, and tetraethylammonium behaves in a fashion similar to that of sodium. At low extracellular concentrations of potassium, ammonium at low concentrations at first stimulates the active potassium influx, but at higher concentrations inhibits it. Tetramethylammonium at most slightly stimulates the active potassium influx, and calcium is without effect. The behavior is consistent with a model in which potassium is required at more than one site before transport occurs, and the sites are indistinguishable as far as their behavior toward the ions investigated is concerned. The affinity of the alkali metal cations for the sites appears to be explicable in terms of their physical characteristics.

Authors

John R. Sachs

Thyroxine Transport in Thyrotoxicosis and Hypothyroidism

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Abstract

(a) The thyroxine-binding proteins were investigated in 23 cases of untreated thyrotoxicosis and 16 cases of untreated hypothyroidism, employing reverse flow paper electrophoresis with the glycine acetate system at pH 8.6 in the Durrum type cell.

Authors

Mitsuo Inada, Kenneth Sterling

Difference in Hepatic Metabolism of Long- and Medium-Chain Fatty Acids: the Role of Fatty Acid Chain Length in the Production of the Alcoholic Fatty Liver

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Abstract

Replacement of dietary triglycerides containing long-chain fatty acids (LCFA) by triglycerides containing medium-chain fatty acids (MCFA) markedly reduced the capacity of alcohol to produce fatty liver in rats. After 24 days of ethanol and MCFA, the increase in hepatic triglycerides was only 3 times that of controls, whereas an 8-fold rise was observed after ethanol and LCFA. The triglyceride fatty acids that accumulated in the liver after feeding of ethanol with MCFA contained only a small percentage of the MCFA; their composition also differed strikingly from that of adipose lipids.

Authors

Charles S. Lieber, André Lefèvre, Norton Spritz, Lawrence Feinman, Leonore M. DeCarli

Chronic Hemolytic Anemia due to Cold Agglutinins: the Mechanism of Resistance of Red Cells to C′ Hemolysis by Cold Agglutinins

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Abstract

The red cells of patients with chronic hemolytic anemia due to cold agglutinins are agglutinated by antiglobulin serum in a nongamma reaction due to the coating of β-globulins, C′4 and C′3. The red cells of such patients are abnormally resistant to C′ hemolysis by cold agglutinin.

Authors

Robert S. Evans, Elizabeth Turner, Margaret Bingham

Qualitative and Quantitative Analysis of Urinary Lipids in the Nephrotic Syndrome

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Abstract

A qualitative and quantitative analysis of urinary lipids in the nephrotic syndrome is presented. The following lipids were identified in the urine of patients with the nephrotic syndrome: free cholesterol, cholesterol esters, triglycerides, free fatty acids, and phospholipids. Glass paper chromatography identified the cholesterol esters as palmitate, oleate, linoleate, and arachidonate, and identified the phospholipids as phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine.

Authors

Saulo Klahr, K. Tripathy, Oscar Bolanos

An In Vitro Effect of Triiodothyronine on Rat Adipose Tissue

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Abstract

Triiodo-L-thyronine (T3) added in vitro to fat pads from normal, or propylthiouracil-treated rats enhanced the rate of release of glycerol and free fatty acids (FFA) in the presence of epinephrine. An effect of T3 was also demonstrated in the presence of adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone, or glucagon in studies with tissue from normal rats. The minimal effective concentration of T3 was approximately 2.5 × 10-5 mole/liter for intact fat pads and 3 × 10-6 mole/liter for fat cells. With fat pads from propylthiouracil-treated rats the effect of T3 was not apparent until the 3rd hr of incubation. Enhancement of epinephrine-stimulated lipolysis by T3 was evident during the 1st hr of incubation of fat pads from normal rats, and fat cells responded almost immediately to the presence of T3. When added alone or in the presence of theophylline, 3′,5′-adenosine monophosphate or its dibutyryl derivative, T3 had little or no effect on lipolysis. The effect of T3 was observed with or without glucose in the medium, and was not inhibited by cycloheximide or actinomycin D. It did not persist when tissues, after incubation in the presence of T3 were transferred to medium without T3. No effect of T3 on glucose uptake in the presence of epinephrine, ACTH, or insulin was demonstrated.

Authors

Martha Vaughan

Human Liver Aldehyde Oxidase: Differential Inhibition of Oxidation of Charged and Uncharged Substrates

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Abstract

Human liver aldehyde oxidase (aldehyde: O2 oxidoreductase, EC 1.2.3.1) has been purified 60-fold and some of its properties studied. Like aldehyde oxidase from other mammalian species, human liver aldehyde oxidase is an enzyme with dual substrate specificity, possessing the ability to catalyze not only the oxidation of aldehydes to the corresponding carboxylic acids, but also the hydroxylation of a number of nonaldehydic heterocyclic compounds; its relative activity towards the latter group of substrates is low, however, when compared with that of liver aldehyde oxidase from rabbit and guinea pig. When the aromatic aldehyde benzaldehyde is used as substrate, human liver aldehyde oxidase, like the rabbit enzyme, is strongly inhibited by menadione, estradiol-17β, antimycin A, Triton X-100, and N-alkylphenothiazines; the human enzyme differs from the rabbit enzyme, however, in being relatively insensitive to oligomycin and Amytal. Like the rabbit enzyme, the human enzyme can catalyze the 3-hydroxylation of phenazine methosulfate (PMS) and the 6-hydroxylation of N-methylnicotinamide (NMN). With the rabbit enzyme, however, the aerobic hydroxylation of these substrates proceeds by a conventional mechanism, while with the human enzyme, the aerobic hydroxylation of PMS and NMN is anomalous in that the reaction is inhibited only by agents with affinity for the substrate-binding site, such as cyanide and N-alkylphenothiazines, and not by agents which inhibit the “internal electron transport chain” of the enzyme, such as menadione and diethylstilbestrol. This mode of oxidation appears to be unique to substrates with a positively charged quaternary nitrogen; the hydroxylation of other nonaldehydic heterocyclic substrates for the human enzyme is sensitive to conventional aldehyde oxidase inhibitors.

Authors

David G. Johns

Experimental Viral Hepatitis in the Dog: Production of Persistent Disease in Partially Immune Animals

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Abstract

Experimental infection with canine hepatitis virus has been studied in a series of 49 dogs. The pattern of response to infection was distinctly modified by the immune status of the animal. All of 19 fully susceptible dogs had an acute, fulminating fatal hepatitis when infected with a standard dose of virus, and all of 19 dogs with high levels of immunity to the virus survived without apparent illness. However, 11 dogs were spontaneously encountered with partial immunity to the infectious agent, and these animals developed different, prolonged forms of hepatitis following infection. In four animals death occurred in 8-21 days following what may be called a subacute course. The remaining seven dogs survived up to 8 months with evidence of chronic hepatic damage. The subacute and chronic forms of hepatitis were reproduced experimentally in seven of eight fully susceptible dogs which were passively immunized against the canine hepatitis virus by administration of hyperimmune serum. Although the virus could be found in sites of hepatic damage in the early stages of the subacute and chronic diseases, it could not be demonstrated in the later stages which were characterized by persistent hepatic damage and a marked chronic inflammatory reaction. Dogs with chronic hepatitis eventually developed extensive hepatic fibrosis. The pathologic, physiologic, virologic, and immunologic features of these experimental forms of viral hepatitis are described.

Authors

D. J. Gocke, R. Presig, T. Q. Morris, D. G. McKay, S. E. Bradley

The Effects of Azathioprine (Imuran) on Purine Synthesis in Clinical Disorders of Purine Metabolism

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Abstract

Azathioprine, a purine analogue, significantly suppressed the purine synthesis de novo of two gouty patients manifesting overproduction of uric acid, as well as three of four gouty patients who showed normal uric acid production. This suppression is taken as evidence that phosphoribosyl-pyrophosphate amidotransferase, the rate-controlling step in purine synthesis de novo, has a normal sensitivity to feedback inhibitors in the patients who responded to the drug.

Authors

William N. Kelley, Frederick M. Rosenbloom, J. Edwin Seegmiller