Gastroduodenal artery aneurysm detected by radionuclide studies

A patient with gastroduodenal artery aneurysm detected with Tc-99m scintiangiography is described. Liver and hepatobiliary imaging were also performed on the patient. Ultrasound examination, arteriography, and surgical exploration were carried out. The value of radionuclide studies in leading to the proper diagnosis is emphasized.

Epsilon-amino-caproic acid in the treatment of Osler's hereditary angioneurotic edema

This clinical entity described for the first time by Osler in 1888 presented a great therapeutic problem during many decades because of its severity. Landerman and later on Donaldson and Evans established the pathogenic mechanisms of this disease finding a deficiency in the inhibitor of the first activated component of complement, an alpha 2 aminoglycoprotein, to be the mechanism responsible of the same. More concretely, alterations in the plasmin, kinin and kallikrein systems are those that will lead to a change in vascular permeability with resultant tissue alterations. Four cases of hereditary angioneurotic edema are studied in female patients aged between 15 and 50 years and with family history consistent with angioneurotic familiar edema in which there were six cases of death due to edema of the glottis. Once the diagnosis had been made the patients were subjected to treatment with EACA at doses of 2.5 gm every 6 hours. The determinations of complement were similar in the four cases, with marked decreases in C4 and C1 inhibitor with a decrease in total complement in three cases. Regarding secondary effects, vomiting was found only in one cases, which as the dose was reduced did not necessitate termination of treatment. In summary, considering the results obtained in the cases above, we believe that due to its good tolerance and moderate cost, epsilon-amino-caproic acid at the abovementioned dosage is an excellent pharmacological agent in the treatment of Osler's hereditary angioneurotic edema.

Nutrition and public health in the Dominican Republic

A nutrition survey was carried out in a mountainous region southwest of Santiago, Dominican Republic, to determine the extent of malnutrition in the area and to obtain information regarding food beliefs and practices needed to design a viable nutrition program. A stratified cluster sampling technique was used to interview 295 mothers of preschool children and examine 448 of their children under five years of age. The incidence of moderate and severe malnutrition was less than expected. Only 12.3% of the children were less than or equal to 75% of the National Center for Health Statistics (NCHS) reference standard for weight/age; however, 6.5% were greater than 110% of the standard. Children from large, poor families were most vulnerable to growth retardation. Definite meal patterns were identified that included varied sources of cereal products and animal and mixed vegetable proteins. Milk and sausage consumption had a significant positive association with all three growth parameters. Suggestions were made for further research and program development.

Negative cooperativity in human liver argininosuccinase

The kinetic properties of argininosuccinase (L-argininosuccinate arginine-lyase, EC 4.3.2.1.) were investigated. Negative cooperativity was observed in the response of the enzyme to the substrate argininosuccinate and GTP behaved as a positive allosteric effector. These effects were observed in 60 mM potassium phosphate but not in 50 mM Tris-HCl. Structural changes in the protein molecule are suggested to explain previous observations of Michaelis-Menten kinetics for this enzyme.

Hybrid, immobilised dimers of human liver arginase

The activity of matrix-bound monomers of arginase (L-arginine amidinohydrolase, EC 3.5.3.1) was not changed by incubation with p-hydroxymercuribenzoate. When the chemically modified, matrix-bound monomers were incubated with soluble subunits in the presence of Mn2+, dimers were obtained. These dimers were hybrids between modified and native monomers. The results obtained are in accord with a D2-symmetry where two dimers meet to form the tetrameric enzyme. From kinetic studies it is concluded that the structure of the active sites of arginase is not affected by the chemical modification with p-hydroxymercuribenzoate.

Evidence for cooperative effects in human liver arginase

The reaction kinetics of human liver arginase (L-arginine amidinohydrolase, EC 3.5.3.1) in terms of arginine concentration is strikingly altered by varying the pH. Lowering the pH from the optimum (9.5) toward a more physiological value (7.5) there is a transition from hyperbolic to sigmoidal kinetics. The cooperative effects are observed in the presence and absence of the product ornithine. Dimers of arginase exhibit typical Michaelis-Menten kinetics even in the presence of ornithine. Dimer-dimer interactions are suggested to explain the kinetic properties of arginase at pH 7.5.

A study of the circadian rhythm in 3, 5 cAMP in bronchial asthma after administration of ketotifen

A study of the circadian rhythm of cAMP is carried out in ten patients suffering from mixed bronchial asthma, with a marked bacterial component and with sensitizations due to pneumo-allergens (house dust and Dermatophagoides). Cyclic AMP levels were determined before and after treatment with Ketotifen (HC-20511). At the same time, cAMP levels were determined in a control group of 10 healthy subjects in order to realize a comparative study with the asthmatic group. Blood was drawn beginning at 5 AM. at four hour intervals for 24 hours. During this period, medication was withdrawn from these patients, although in some cases antibiotics and mucolytics were administered later; these same patients were treated with Ketotifen in a dose of 1 mg every 12 hours for 5 days. In the blood samples, cAMP levels were determined through a method based on Gilman's technique (comparative protein binding) using the Cyclic AMP Assay Kit (The Radiochemical Center, England). Among the results obtained, there is a clear elevation of cAMP levels in all the determinations after the administration of Ketotifen, maintaining the circadian rhythm with a maximum peak in cAMP levels 5 hours after the drug was given. Thus an increase in all values when compared with basal levels were found arguing in favour of a protective action of this substance carried out through stabilization of the mast cell membrane and thus impeding the release of histamine.

Proteins specified by African swine fever virus. I. Analysis of viral structural proteins and antigenic properties

At least 28 polypeptides have been identified in intracellular virus, with molecular weights ranging from 11,500 to 243,000 daltons. By treatment with Nonidet P-40 and 2-mercaptoethanol it is possible to obtain subviral particles that have lost some proteins and have a density in CsCl of 1.31 g/cm3 which is higher than that of the complete virus (1.23 g/cm3). After addition of NaCL the virus loses its major protein VP73 which indicates that it is localized in the viral envelope. Cores obtained after this treatment are made up of at least 14 proteins. Incorporation of 3H-fucose and 3H-glucosamine in intracellular virus occurs in three minor components. The protein VP42 is possibly the cell actin and appears to be strongly associated with the virus. It is not possible to eliminate it under conditions where the viral envelopes disappear morphologically. At least the proteins VP172, VP162, VP146 and VP73 act as antigens in the natural infection.

Subunit interactions and immobilised dimers of human liver arginase

Incubation of soluble human liver arginase (L-arginine amidinohydrolase, EC 3.5.3.1) with p-hydroxymercuribenzoate resulted in the dissociation of the enzyme into active dimers. Addition of 2-mercaptoethanol resulted in the regeneration of the tetrameric enzyme. When arginase, bound covalently to nylon, was incubated with p-hydroxymercuribenzoate, matrix-bound dimers were obtained. Incubation of these species with 2-mercaptoethanol resulted in stable, unmodified dimers. Based on this dissociation of arginase, a model with D2-symmetry is suggested for this enzyme. The specific activity, the Km value for arginine, pH optimum and the inhibition constants for ornithine and lysine were determined for monomeric, dimeric and tetrameric forms. It is concluded that the behaviour of the active sites of the monomers is not substantially altered by the interaction of these species in the oligomeric molecule.

Scanning electron microscopic investigations of olfactory epithelium in the chick embryo

This paper describes maturation of the surface of the olfactory epithelium of the superior nasal concha of chick embryos from the seventh day of incubation till hatching. From the earliest stages investigated onward, the apical surface of the olfactory epithelium is characterized by variability in the number and configuration of surface protrusions. The growth of olfactory cilia is described and the significance of regional differences in their density is discussed in relation to regional variations in the sensitivity of the epithelium to odorants. The maturation of the respiratory epithelium covering the inferior nasal concha is also described.

The penetration of sodium into the epithelium of the frog skin

The aim of this paper is twofold. First, to describe a method for the measurement of the unidirectional flux of Na from the outer bathing solution into epithelium (J(OT)), and second, to describe the use of this method under a variety of experimental conditions in order to obtain some insight into the nature of this flux. The method developed is based on the exposure of a frog skin to a Ringer solution containing (22)Na. The exposure is made so that neighboring points along the surface remain in contact with the (22)Na solution for gradually longer periods, ranging from 0 to 46 sec. Some 8 to 10 samples of the exposed part are used to obtain the time course of the uptake of (22)Na and this time course is used, in turn, to evaluate J(OT). This flux is then studied in skins mounted between two identical Ringer solutions with 115 mM Na (11.25 +/- 0.10 [18] micromole.hr(-2) cm(-2)), and in skins mounted with Ringer with 1 mM Na on the outside and 115 mM Na on the inside (0.43 +/- 0.05 [18] micromole.hr(-1).cm(-2). From the observations that the flux is much larger than the net Na flux across the whole skin, that it is inhibited by K(+), and is unaffected by ouabain, it is concluded that the penetration of Na(+) into the epithelium does not occur by simple diffusion and is not directly dependent on an ouabain-sensitive mechanism. In the course of these experiments it was observed that when the skin was crushed between two chambers the uptake of Na in the neighboring exposed areas was decreased.