Showing papers by "Saint Louis University published in 1969"

Selective Passage of Prostaglandins across the Lung

Abstract: STIMULATION of the splenic nerves releases prostaglandins from the spleen to give concentrations of as much as 0.2 µg/ml. in splenic venous blood1. The release of prostaglandins might influence organs remote from the site of release, for prostaglandins can exert potent actions on smooth muscle2. The lung has recently been shown to determine the fate of many vasoactive substances; some are activated—conversion of angiotensin I to angiotensin II (ref. 3)—and some inactivated. The degree of inactivation seems to be specific for a given substance, ranging from almost complete (bradykinin4, 5-hydroxytryptamine5, prostaglandins E1 E2 and F2α (ref. 1)), to minor (noradrenaline6), to allowance of their free passage (adrenaline6 and angiotensin II (ref. 7)). The removal of prostaglandins by the lung restricts their activities to the organs from which they are released and between their organ of origin and the site in the pulmonary circulation where they are inactivated1. A prostaglandin which passed through the lungs after its release from an organ could be considered a circulating hormone, as long as it is not rapidly degraded in the blood. Ferreira and Vane1 reported that prostaglandins E1 E2 and F2α were stable in blood, though rapidly inactivated by the lung. Removal of prostaglandins A1 and A2 by the lung was not determined because the assay organs are insensitive to them. Vascular smooth muscle, however, unlike other smooth muscle, is reactive to low concentrations of prostaglandins A1 and A2 (refs. 8–10) and the renal vasculature is probably most sensitive to prostaglandins A1 and A2 (refs. 10 and 11). Because the renal vasculature is also sensitive to prostaglandins E1 and E2 (ref. 12), it has been used as an index of the fate of prostaglandins infused into the venous and arterial circulations.

World as View and World as Event

Abstract: As a concept and term, “world view” is useful but can at times be misleading. It reflects the marked tendency of technologized man to think of actuality as something essentially picturable and to think of knowledge itself by analogy with visual activity to the exclusion, more or less, of the other senses. Oral or nonwriting cultures tend much more to cast up actuality in comprehensive auditory terms, such as voice and harmony. Their “world” is not so markedly something spread out before the eyes as a “view” but rather something dynamic and relatively unpredictable, an event-world rather than an object-world, highly personal, overtly polemic, fostering sound-oriented, traditionalist personality structures less interiorized and solipsistic than those of technologized man. The concept of world view may not only interfere with the empathy necessary for understanding such cultures but may even be outmoded for our own, since modern technological man has entered into a new electronic compact with sound.

Acute hemangioma-like lesions associated with echo viral infections

Abstract: In the summer and fall of 1968, during clinical rubella vaccine trials, clinical and laboratory surveillance of acute exanthematous illnesses was carried out. During this period, four children with acute transitory hemangioma-like lesions were noted; ECHO 25 virus was isolated from two of these patients and ECHO 32 was recovered from the other two children. All four children had four- fold or greater neutralizing antibody titer rises to their respective viruses. It is suggested that the individual lesions of the reported exanthems have a pathogenesis similar to other enteroviral maculopapular eruptions, except that vascular dilatation is arteriolar as well as capillary.

Parallel Response of Myofibrillar Contraction and Relaxation to Four Different Nucleoside Triphosphates

Abstract: The Mg chelates of ITP, GTP, and UTP in addition to that of ATP were shown to be capable of causing complete relaxation of myofibrils as indicated by the complete inhibition of syneresis and the reduction of the NTPase activity to that of isolated myosin. For ITP and GTP the required concentrations were about 100 times higher than those for ATP, whereas UTP was maximally effective also in low concentrations (0.2 mM). For all NTP's the concentrations for relaxation were related to those necessary for contraction so that NTP concentrations which gave 80–90% maximal NTPase activity in the presence of Ca caused complete relaxation in the absence of Ca. Thus, these experiments do not support the view that relaxation is caused by the binding of NTP to a special inhibitory site but are quite compatible with the idea that relaxation depends on the extent to which the hydrolytic site is saturated with NTP. The Ca concentration required for contraction depends on the nature of the NTP base and its concentration; it is lower for ITP than for ATP and decreases with decreasing concentrations of ITP.

Heart transplantation in primates.

Abstract: Although reconstructive procedures for congenital and acquired cardiac deformities of the heart have developed rapidly in the past decade, there remain many conditions that are not amenable to repair. For such conditions, cardiac substitution offers promise. Substitution might take the form of a mechanical device or a transplanted heart. The feasibility of cardiac transplantation in the dog has been studied extensively by ourselves and others.7,8,11,13j15 In this animal a number of structural, functional, chemical, and metabolic changes occur as a result of severing the extrinsic cardiac inner~ation.2-~.12,l*~~7~~~ These changes, although at times profound, are nonetheless well tolerated because of compensatory mechanisms; long-term survival is regularly attained in dogs with cardiac autotransplantation. In cardiac homotransplantation the limiting factor is immunological rejection. Immunosuppression in dogs has permitted survival of cardiac homotransplants for many months,lJO but only at the expense of making the animals immunologic cripples. We have, therefore, extended our investigations to primates in an attempt to determine if this order tolerates the procedure as well as dogs and to study in this order the rejection phenomenon and its relation to immunosuppressive therapy. Excision and reimplantation of the heart (autotransplantation) has been performed in 18 Kenya baboons (Papio cynocephalus) . In addition, homotransplantation (allotransplantation) of the heart has been performed in two baboons. The method of transplantation we have described in dogs includes division of the aorta and pulmonary arteries just distal to the valves, division of the left atrium at the confluence of the pulmonary veins, and transection of the two cavae close to the heart.16 The heart is arrested by cold, lactated Ringer's solution. The coronary arteries are not perfused during the 40-50 minutes of arrest. All structures are resutured in their original position. Circulation and oxygenation to the body are provided by means of a pump and bubble oxygenator with the perfusate at 20\" C. The extracorporeal unit is primed with 500 cc 5 % dextrose in water, 250 cc 5% dextrose in saline, and 300 cc of type specific whole blood. Anticoagulation is obtained before perfusion by giving heparin, 1 mg/lb body weight. This is neutralized after perfusion by protamine sulphate, 1 mg/lb body weight. The animals tolerate the 60-90 minutes of extracorporeal circulation quite well. Blood loss after perfusion is generally small; transfusion of blood is seldom needed, and the amount never exceeds 250 cc. For several weeks the animals maintain their weight or gain slightly; thereafter, they lose one to four pounds before regaining their initial weight. There was evidence of extravascular fluid collection in one animal that died under anesthesia during cardiac catheterization two weeks after operation. At autopsy there were 800 cc of pleural fluid and ascites of a liter.

Formation of gigantic mitochondria in hypoxic isolated perfused rat hearts

Abstract: Herzen gesunder, erwachsener Ratten wurden mit Krebs-Henseleit-Bikarbonatlosung durchstromt (95% O2∶5% CO2) Bei kunstlich herbeigefuhrter Hypoxie (95% N2∶5% CO2) erschienen die Herzmitochondrien innerhalb von 7 min bedeutend vergrossert und zu 25% miteinander verschmolzen

Possible X-Linked Congenital Heart Disease

Abstract: Four male members of a family are known to have congenital mitral and aortic insufficiency, a fifth male has congenital mitral insufficiency only, and a sixth male had congenital heart disease by history. The involved males comprised all males in three generations of this family. Chromosomal and dermatoglyphic studies of the two living affected males are normal. The involvement of males in this family is best explained on the basis of X-linked recessive inheritance. To our knowledge, this is the first report of possible X-linked inheritance of isolated congenital heart disease.

Primary structure of transfer RNA.

Abstract: The primary structures of fourteen different tRNAs are compared and a generalized structure is proposed which might apply to all tRNA molecules.

The "emphysema profile" in two midwestern cities in North America.

Abstract: A comparison of St. Louis and Winnipeg was made. St. Louis put out 13 times greater SO/sub x/, 7 times greater NO/sub x/, 6 times greater hydrocarbons, and twice the particulate (dustfall). Also, the St. Louis climate favors inversion and discourages dispersion. A study of 300 lungs by autopsy was performed. St. Louis had more emphysema cases: 7 times as many among 20- to 49-yr-olds, 2 times as many among 50- to 69-yr-olds, and 1.5 times as many in over-70 age group. Also a difference in severity was noted. Severe emphysema is uncommon in Winnipeg, whereas severe cases were encountered in every age group in St. Louis. No severe emphysema in non-smokers was found in either city. A synergistic effect between smoking and pollution is suggested.

Bacteriophage-induced Inhibition of Host Functions II. Evidence for Multiple, Sequential Bacteriophage-induced Deoxyribonucleases Responsible for Degradation of Cellular Deoxyribonucleic Acid

Abstract: Degradation of bacterial deoxyribonucleic acid (DNA) after infection with T4 bacteriophage was studied in an endonuclease I-deficient host. The kinetics of degradation were similar to those seen in other hosts with a normal level of this enzyme. Irradiation of extracellular phage with ultraviolet (UV) destroyed the capacity of the infecting virus to induce extensive breakdown of host DNA, which was, however, converted to high-molecular-weight material. Addition of chloramphenicol to T4-infected cells provided data which can be interpreted to indicate the involvement of at least two endodeoxyribonucleases and one exodeoxyribonuclease having a high degree of specificity. A model is proposed showing the sequential action of two endodeoxyribonucleases followed by an exodeoxyribonuclease in the degradation of host DNA. The appearance of these hydrolytic enzymes requires protein synthesis. Infections leading to partial degradation only (UV-irradiated phages, gene 46 mutants) effectively inhibited the synthesis of bacterial messenger ribonucleic acid and of β-galactosidase.

Semantic Determinants of Pauses

Abstract: The following experiment presents evidence that variations in semantic context can produce changes in the rate and length of pauses in a situation in which syntactic and other variations are minimized. Each of 40 Ss read two paragraphs aloud and after each paragraph retold the “story” without further instructions. Each paragraph consisted of five sentences, each containing 23 syllables. The third sentence was either in accord with the story or an unusual occurrence (depending on exchange of subject and object). The most important experimental finding was that both number and length of unfilled pauses are more frequent throughout the unusual stories as compared with the usual ones. In the readings, the effect was limited to the critical sentence and the pauses immediately thereafter. The evidence supports the view of the authors that the role of semantic context has been underestimated in psycholiguistic research to date.

Magnesium deficiency in protein-calorie malnutrition: a follow-up study.

Abstract: Protein-calorie malnutrition (PCM) , the major nutritional deficiency syndrome of the world, is responsible for appalling morbidity and mortality among the underprivileged children of developing nations in the tropics and subtropics. The history and clinical features of patients with PCM are remarkably similar throughout the world. The patients are breast-fed for about two years, or according to local custom, and at weaning time receive a bland low protein diet, chiefly of vegetable origin. Gastroenteritis may initially be attributed to poor sanitary conditions, but as malnutrition progresses, the attacks recur with increasing frequency, usually with no known pathogenic agents. During episodes of gastroenteritis, the diet is strictly limited to starch and water, and therapeutic purges for suspected intestinal parasites may be routine. By the second or third year of life, the child may be irritable, anorexic, and emaciated and may have peripheral edema, skin lesions, and other variable features: PCM is then

Prostaglandins and Natriuresis: the Effect of Renal Prostaglandins on PAH Uptake by Kidney Cortex

Abstract: THE plasma of dogs loaded with saline seems to contain a “natriuretic hormone” which inhibits the reabsorption of sodium by the proximal renal tubule in the rat1. It also seems that plasma from dogs infused with saline will inhibit the uptake of para-aminohippurate (PAH) by slices of rabbit kidney cortex2. We have tried to determine the relationship between these two factors. One class of compounds which has properties common to “natriuretic hormone” and the factor inhibiting PAH uptake is the prostaglandins. Both “natriuretic hormone” and prostaglandins are dialysable and produce an increase in sodium excretion1,3ndash;5. In addition, prostaglandins are capable of exhibiting a 280 mmicron chromophore which is the absorption peak at which Bricker et al. observed inhibition of PAH by saline expanded plasma2. In order to relate prostaglandins, “natriuretic hormone” and the PAH inhibiting factor, we have studied the effect of prostaglandins on PAH accumulation by rabbit kidney cortex in vitro.

Effects of stimulus order and novelty on orienting responses.

Abstract: The effects of stimulus order and novelty upon habituation and dishabituation of the GSR component of the OR were investigated. The numbers 21 to 60 were presented in serial order (Ordered-Novel group), and in random order (Random-Novel group), and the number 21 was repeated 40 times (Similar group). The number 600 was occasionally interpolated among each series. No group differences in magnitude of OR to the first stimulus or in habituation of the OR during the series of numbers were found. Dishabituation due to the interpolated stimulus was found primarily in the Similar group. The results were related to Sokolov's concept of neuronal models used in his theory of habituation.