Isolation of canine prolactin by polyacrylamide gel electrophoresis

The electrophoretic mobility of prolactin obtained from canine pituitary extract was studied with the aid of polyacrylamide disc electrophoresis. Using a preparative gel electrophoretic system the immunoreactive material was purified on a quantitative scale which was then used to develop a homologous radioimmunoassay for canine prolactin. The radioimmunoassay system was able to detect prolactin in the plasma of dogs after the administration of agents which would be expected to affect prolactin secretion.     

Anatomic correction of transposition of the great vessels

We present a new approach for anatomic correction of transposition of the great arteries. The two coronary arteries, with a piece of the aortic wall attached, are transposed to the posterior artery. The two aortic openings are closed with a patch. The aorta and pulmonary artery are transected, contraposed, ant then anastomosed. The interventricular septal defect is closed with a patch, through a right ventriculotomy approach, because the right ventricle is no longer part of the systemic circulation. Two patients, aged 3 months and 40 days weighing 4,200 and 3,700 grams, respectively, were operated upon with deep hypothermia and total circulatory arrest. There was good recovery from the operation, with normal cardiocirculatory conditions. Renal failure developed in the first patient, and she died on the third postoperative day. During this time the cardiocirculatory conditions were good. The second patient made an uneventful recovery. Hemodynamic studies 20 days after the operation showed complete correction of the malformation. Five and one-half months after the operation, he weighs 7,500 grams, and his development is very good. We believe that this operation will be reproducible by most cardiovascular septal defect and pulmonary hypertension.     

On reliability of prediction in linear models

For a linear noisy system assume an estimatehat{beta}of the unknown parameter vector was obtained from a certain past data on inputs and outputs of the system. The prediction of the output for any input vectorxis a linear combination ofxandhat{beta}. The question of concern is: For what - values of the inputs would the error in their predicted outputs be the smallest? It is found that they are the inputs which lie on the fitted plane of the orthogonal regression among the past data of the clean inputs.     

Ultrastructural studies in epidermolysis bullosa hereditaria. III. Recessive dystrophic types with dermolytic blistering (Hallopeau-Siemens types and inverse type)

In this paper the authors describe and analyse results that they obtained by infection of the guinea pig organism carried out by subcutaneous or intratracheal application with five mycobacterial strains, namely Myco bovis BCG-Praha, Myco the H37Ra, Myco Kansasii, Myco fortuitum and Myco smegmatis. At predetermined time intervals following subcutaneously or intratracheally performed infection (on 7th, 16th, 28th and 56th day after infection) transplantation of a Deals' guinea pig sarcoma cell suspension was carried out in guinea pigs by the intraltracheal route. As it appears from the results gained the applied mycobacteria exhibit a partial inhibition of growth od Deals' guinea pig sarcoma cells of different character. From among the utilized strains the Myco bovis BCP-Praha and the Myco tbc H37Ra exhibited the highest, Myco fortuitum and Myco smegmatis the lowest inhibitory activity. Intratracheally performed infections yielded in general better results on the growth inhibition than infections carried out with the same strain but by the subcutaneous route. Furthermore, in the experiments reported on in the present paper the authors could verify their earlier experience, namely that inhibition of growth of sarcoma cells is most pronounced at the time of maximal biological activity (logarithmic phase of multiplication) of the applied mycobacterium.     

Pancytopenia and aplastic anemia: a retrospective study

During January 1971--June 1975 we examined 195 patients with pancytopenia. The cause was bone marrow failure in 67.7% of cases (classic aplastic anaemia in 11.3%) hypersplenism in 7.7%, massive blood transfusions in 1.5%, severe infections in 9.7% (Gram-negative in 3%), and various other conditions in 7.8%. Records were insufficient for diagnosis in 5.6% of cases. Analysis of the 22 patients with aplastic anaemia showed no apparent aetiology in 16 (72.7%), previous phenylbutazone ingestion in 2, and Fanconi-type anaemia in 4 of 7 children. One-year survival was 73.7%, 2-year survival 71.4%, 3-year survival 63.6% and 4-year survival 57.1%. Marrow-investigation of the 21 available samples showed that 6 were acellular, 11 hypocellular and 4 normocellular. All patients received at least temporary therapy with anabolic steroids but its effectivity could not be satisfactorily assessed. Five patients died within 7 months and 5 patients went into remission, needing no further therapy. The initial haematological features of the 5 patients who died were not significantly different from those of the rest of the patients.     

On the question of an electrokinetic requirement for phospholipase C action

The phospholipase C of clostridium welchii (alpha toxin) has an absolute requirement for trace quantities of Ca2+. It attacks pure phosphatidylcholine particles (smectic mesophases) having a close-packed bilayer structure only when their surface zeta potential is made positive by the addition of certain divalent ions (e.g., Ca2+) to the aqueous phase or by the presence of low concentrations of long chain cations to the lipid. Alternatively, if the rotational freedom of individual phospholipid molecules is increased by the insertion of short n-alkanols (e.g., hexanol) into the bilayer or when a monolayer of the substrate at an air/water interface is expended, enzymic hydrolysis can occur without any requirement for a net postive charge on the surface.     

A Comparative Study of the In Vitro and In Vivo Release of Dexamethasone from a Spray-On Bandage and Timed Release Aerosol

The formulation of several dexamethasone topical delayed release aerosol preparations was studied. Ethylcellulose and tributyl citrate were the film-forming agent and plasticizer, respectively, for the spray-on bandage formulation. The aerosol timed release preparation contained dexamethasone microcapsules suspended in a fluorocarbon aerosol propellant by isopropyl myristate and fumed silica. Both preparations were evaluated using an in vitro method which measured the release of dexamethasone hourly for eight hours. In vitro studies showed that each of the formulations delayed the release of dexamethasone. In the in vivo tests aerosols were sprayed on the unabraded back area of rabbits and the increased 17 - hydroxycorticosteriod urine levels at 24, 48, and 72 hours indicated dexamethasone absorption. In vivo studies indicated that absorption did not occur with the timed release preparation containing dexamethasone microcapsules. However, dexamethasone from the spray-on bandage preparation was absorbed over 72 hours. A commercially marketed topical dexamethasone cream was used for comparison in evaluating the two experimental formulations; however, in vivo studies showed that no absorption occurred with this preparation.

In recent years, a great deal of work has been directed towards the application of medicated polymeric films or tissue adhesives onto the skin to treat minor dermatological problems or serious skin wounds. Among the factors to be considered are: incorporation of a specific active ingredient, the mode of application and the dosage form. Lange and Fang (1,2) developed spray-on bandages using water soluble resins and water as the solvent. Fischl (3) evaluated the effectiveness of a cyanoacrylate monomer in closing skin incisions without affecting wound healing. Bhaskar and Cutright (4) showed that butyl cyanoacrylate could be successfully used as a surface dressing while reducing the degree of inflammation. Sciarra and Gidwani (5,6) reported on the release of gentian violet from selected polymer and plasticizer combinations and established various polymer-plasticizer combinations which could be applied as an aerosol spray. Other studies (7,8) have shown that ethylcellulose and a thermoplastic polyamide resin have potential use in spray-on bandage formulations.

The results indicated that the anti-infectives were released from the films and the spray-on bandages reduced the degree of infection about the wound.

The process of microencapsulation has been applied to various industrial and medical uses. Microcapsules can be prepared so that the encapsulated material will be released slowly. There are various methods of microencapsulation including coacervation, phase separation, interfacial polymerization, an electrostatic method, and vacuum metalization and they have been successfully used with selected drugs (9-13).

The purpose of this study was to develop and evaluate different aerosol formulations containing a therapeutic agent which can be slowly released. In vitro and in Vivo systems were used to evaluate the release and absorption of the drug in the test animals.