bluuebunny/crossref_metadata_2025 huggingface dataset:
NAD(P)H Oxidase–Derived Superoxide Mediates Hypercholesterolemia-Induced Leukocyte–Endothelial Cell Adhesion
Authors: Stokes Karen Y. , Clanton E. Chris , Russell Janice M. , Ross Chris R. , Granger D. Neil
Published: June 2012

Abstract
—Experimental animals placed on a high-cholesterol diet for 2 or more weeks exhibit an inflammatory response in postcapillary venules. The aims of this study were to determine (1) whether superoxide mediates the hypercholesterolemia-induced inflammatory response and (2) whether leukocyte and/or vessel wall NAD(P)H oxidase contributes to this response. Intravital videomicroscopy was used to quantify leukocyte–endothelial cell adhesion in cremasteric postcapillary venules of wild-type (WT) mice, CuZn-superoxide dismutase transgenic (SOD TgN) mice, and mice heterozygous (p47

phox

+/−) or homozygous (p47

phox

−/−) for NAD(P)H oxidase placed on either a normal diet or high-cholesterol diet (HCD) for 2 weeks. The number of adherent and emigrated leukocytes in postcapillary venules of WT HCD mice was significantly higher than that detected in venules of their normal-diet counterparts. However, the HCD-induced recruitment of adherent and emigrated leukocytes was not observed in SOD TgN mice. Whereas hypercholesterolemic p47

phox

+/− and WT mice exhibited similar inflammatory responses, p47

phox

−/− mice did not. Bone marrow chimeras were developed to selectively delete p47

phox

from either the vessel wall or circulating leukocytes. Whereas WT marrow transplanted into WT mice produced a normal inflammatory response of venules to HCD, chimeric mice with p47

phox

deficiency in either the vessel wall or leukocytes exhibited an attenuated inflammatory response to HCD that was comparable with that observed in p47

phox

−/− HCD mice. Our findings indicate that enhanced superoxide production is a critical event that initiates the leukocyte–endothelial cell adhesion in postcapillary venules of HCD mice. NAD(P)H oxidase appears to be an important source of this superoxide.
Reperfusion-Activated Akt Kinase Prevents Apoptosis in Transgenic Mouse Hearts Overexpressing Insulin-Like Growth Factor-1
Authors: Yamashita Kazuhito , Kajstura Jan , Discher Daryl J. , Wasserlauf Bernard J. , Bishopric Nanette H. , Anversa Piero , Webster Keith A.
Published: June 2012

Abstract
—Hearts of wild-type and insulin-like growth factor-1 overexpressing (Igf-1
+/−
) transgenic mice were subjected to Langendorff perfusions and progressive periods of ischemia followed by reperfusion. Apoptosis was measured by DNA nucleosomal cleavage and a hairpin probe labeling assay to detect single-base overhang. Transgenic hearts subjected to 20 minutes of ischemia and 4 hours of reperfusion (I/R) sustained a rate of apoptosis of 1.8±0.3% compared with 4.6±1.1% for wild-type controls (n=4;
P
<0.03). Phosphorylation of the protein kinase Akt/protein kinase B was elevated 6.2-fold in transgenic hearts at baseline and increased another 4.4-fold within 10 minutes of reperfusion, remaining elevated for up to 2 hours. I/R activated Akt in wild-type hearts but to a lesser extent (1.6±0.3-fold). Pretreatment of transgenic hearts with wortmannin immediately before and during ischemia eliminated reperfusion-mediated activation of Akt and neutralized the resistance to apoptosis. The stress-activated kinase p38 was also activated during ischemia and reperfusion in both wild-type and transgenic hearts. Perfusion with the p38 inhibitor SB203580 (10 μmol/L) blocked both p38 activation and phosphorylation of Akt and differentially modulated apoptosis in wild-type and transgenic hearts. Pretreatment with SB203580 reduced apoptosis in wild-type hearts but increased apoptosis in transgenic hearts. These results demonstrate that Akt phosphorylation during I/R is modulated by IGF-1 and prevents apoptosis in hearts that overexpress the IGF-1 transgene.
Potassium and Its Effect on Glycogen in the Dog Heart
Authors: MERRICK ARTHUR W.
Published: June 2012

Potassium chloride, infused into 10 anesthetized dogs until severe electrical changes were observed in the heart (electrocardiogram) and serum potassium was elevated (9.5 mEq./L.), had no apparent effect on the glycogen content of any of the 4 heart chambers. Dog ventricular slices did not tolerate a medium high in potassium. Glycogenolysis was noted when the slices were incubated in a Krebs-Ringer buffered phosphate glucose medium containing 9 mM of potassium. The glycogen loss was confined to the acid-soluble form of the polysaccharide. A homogenate of dog myocardium, incubated in a simulated "intracellular" medium for up to 50 minutes, rapidly and continuously lost acid-soluble glycogen. The acid-insoluble fraction was not degraded until the homogenate was incubated for 50 minutes.
Tension Developed by Papillary Muscles from Hypertrophied Rat Hearts
Authors: KERR ANDREW , WINTERBERGER ALAN R. , GIAMBATTISTA MARY
Published: June 2012

Papillary muscle strips from hypertrophied left ventricles of 17 rats were tested for tension developed in response to electrical stimulation in a perfused, oxygenated, isometric muscle chamber. The maximum tension developed was significantly greater per unit weight than that developed by papillary muscles from normal ventricles. Greater tension was also developed by the papillary muscles from hypertrophied hearts when tested with an anaerobic perfusate.
Effect of Meal Eating Compared to Nibbling upon Atherosclerosis in Chickens
Authors: COHN CLARENCE , PICK RUTH , KATZ LOUIS N.
Published: June 2012

Both the production and regression of experimental atherosclerosis, as influenced by eating habits, were studied in the chicken. Birds were either allowed free access to food 24 hours/day ("nibblers") or only for two one-hour periods per day ("meal eaters"). In the induction experiments, it was found that the meal eaters exhibited double the serum cholesterol levels and seven times the severity of coronary atherosclerosis as the nibblers. In studies designed to explore the effects of these eating habits on the regression of established atherosclerosis, lesions were induced in the usual way by feeding an atherogenic diet under the conditions of meal eating. Then the birds were put on regular mash and divided into two groups: meal eaters and nibblers. Meal eating a regular mash diet was associated with (a) slower rate of fall of serum cholesterol levels to normal, and (b) a marked decrease in the rate of healing of the coronary lesions as compared to nibbling. It is concluded that the manner of ingestion of the diet plays a significant role in accentuating the production and in inhibiting the regression of experimental atherosclerosis.
Effect of Hematocrit on Venous Return
Authors: GUYTON ARTHUR C. , RICHARDSON TRAVIS Q.
Published: June 2012

In 18 dogs, the major factors besides blood hematocrit that are known to affect venous return were exactly controlled, while the hematocrit itself was varied from 9.5 up to 65. In general, the changes in venous return in these experiments were approximately the reciprocal of the changes in blood viscosity, as estimated from standard blood viscosity curves. An interesting sidelight of these studies was the fact that the minute volume of red blood cells transported by the arterial blood to the tissues, as calculated by multiplying the hematocrit times the venous return, reached a maximum at a hematocrit of 40. The minute volume of red blood cells fell drastically in anemia because of decreased hematocrit and in polycythemia because of greatly reduced venous return.
Pathogenesis of "Electrolyte-Steroid-Cardiopathy"
Authors: NICKERSON MARK , KARR GERALD W. , DRESEL PETER E.
Published: June 2012

The production of acute necrotic lesions of the myocardium and concomitant changes in myocardial and skeletal muscle potassium concentrations were investigated in rats. Lesions were induced by the administration of 2α inethyl-9α-chlorocortisol plus oral Na
2
SO
4
(which caused a profuse catharsis), steroid plus an irritant cathartic (croton oil), steroid plus low-potassium diet, and low-potassium diet alone. Lesions in the various groups were grossly and microscopically indistinguishable. Their incidence and severity were well correlated with the degree of myocardial potassium depletion below a threshold value of approximately 72 mEq./Kg. wet weight. Skeletal muscle potassium was decreased roughly parallel to that of the myocardium, but some what more variably. Other treatments, including steroid or oral Na
2
SO
4
alone and steroid plus subcutaneous Na
2
SO
4
which failed to produce comparable reductions in myocardial potassium, failed to induce morphological lesions. Any specific interaction between steroid and electrolyte in the production of the myocardial lesions appears to be ruled out by the ineffectiveness of Na
2
SO
4
administered sub cutaneously. It is concluded that the "electro lyte-steroid-cardiopathy" results from a simple intracellular potassium deficiency and its sequelae, and that the roles of the steroid-cathartic electrolyte, and other agents and procedures are to induce potassium depletion by various mechanisms.
Epicardial Excitation Pattern as Observed in the Isolated Revived and Perfused Fetal Human Heart
Authors: DURRER D. , BÜLLER J. , GRAAFF P. , Lo G. I. , MEYLER F. L.
Published: June 2012

The resuscitated fetal human heart can be used as an experimental tool for the investigation of the excitatory process in the human heart. During perfusion the configuration of the epicardial electrocardiograms does not change appreciably. For accurate recording permitting a detailed analysis, the use of a high-fidelity oscillograph is absolutely necessary, otherwise no identification of the rapid portion of the intrinsic deflection can be made. The heart is suspended in an homogenous volume conductor at 37 C. and perfused with fluid matching as closely as possible the composition of the extracellular fluid.

The morphology of the unipolar complexes is difficult to describe adequately. At the anterior side of the right and left ventricles rS complexes are found. Some parts of the left ventricular wall and posteroapical region of the left ventricle show QR complexes. In the area bordering the A-V groove one-third the distance from apex to basis, deep Q waves and even QS complexes are found. The relatively late intrinsic deflection here points to late excitation of this region. In regions neighboring the A-V groove, the Q wave diminishes in size and the R increases. The left posterior part of the left atrium is activated latest in the atrial cycle. The epicardial excitation pattern is surprisingly simple. The excitation wave reaches the region of attachment of the right anterior papillary muscle first, then spreads radially with varying velocity across the left ventricle towards the posterobasal region, while another wave spreads simultaneously across the right ventricle towards the same region. There is, therefore, a double envelopment of the epicardial surface. A comparison of the complexes having an intrinsic deflection occurring at the same time shows conclusively that, even over the same ventricle, the morphology of these complexes may be completely different. Thus the excitation time does not determine the morphology of the complexes. There is no typical right or left ventricular pattern. There appears to be no relationship between thickness of the heart wall and height of the R wave.
Flow, Pressure, and Volume Relationships in the Pulmonary Circulation During Exercise in Normal Dogs and Dogs with Divided Left Pulmonary Artery
Authors: MARSHALL ROBERT J. , WANG YANG , SEMLER HERBERT J. , SHEPHERD JOHN T.
Published: June 2012

The effect of exercise on the pulmonary circulation was studied in a group of 6 intact dogs and in a second group of 4 subjected to ligation and division of the left pulmonary artery. Observations were made with the dogs standing and running on a horizontal treadmill up to the maximal speed they could maintain for periods of at least 2 minutes, usually 12 or 14 km./hr.

Continuous records were made of the difference in pressure between the main pulmonary artery (PA) and a pulmonary-artery wedge (PAW) position. Cardiac output was determined by the indicator-dilution method, with injection of indocyanine (cardiogreen) dye into the main pulmonary artery and continuous sampling from the root of the aorta. The mean transit time of indicator betweell the pulmonary and aortic valves was obtained from the dilution curves, a correction being made for the transit time through the sampling apparatus. From these measurements the blood volume of the lungs and left heart chambers was derived.

In the intact dogs, cardiac output increased approximately threefold from rest to severe exercise. There was an increase of only 12 per cent to 50 per cent in PA minus PAW pressure. Thus a continued fall occurred in pulmonary vascular resistance. The blood volume of the lungs and left heart of 3 intact dogs was measured. In 2 it did not change through the range of activity, and in the third the increase with maximal exercise was 18 per cent.

The dogs with ligated left pulmonary artery also showed a threefold increase in output with severe exercise. Since the entire output passed through a single lung, the effect on the pulmonary vessels was comparable to that of a sixfold increase in output in a normal dog. Despite such large flows, in 3 of 4 dogs the difference between PA and PAW pressure rose only 37 per cent to 50 per cent. The volume of blood in the lungs and left heart was unchanged between rest and 8 km./hr., and at higher speeds showed a 0 per cent to about 20 per cent increase.
Effect of Conditioned Anxiety Upon the Behavior, Blood Lipid Level, and Atherosclerosis of Cholesterol-Fed Cockerels
Authors: JOYNER CLAUDE R. , BULLOCK DONALD H. , RAWNSLEY HOWARD M. , BRUNT MANLY Y.
Published: June 2012

Cholesterol-fed cockerels were subjected five days of each week to repetitive unavoidable shocks preceded by warning signals. The birds rapidly developed the intended conditioned emotional reaction. Comparison of these chicks with nonstressed cholesterol-fed cockerels over several months gave no iadication that this type of stress influenced weight gain, blood lipid level, or the development of atherosclerosis.
Distribution of Blood Flow in the Digestive Tract of the Rat
Authors: STEINER SHELDON H. , MUELLER GUSTAVE C. E.
Published: June 2012

The rubidium fractionation technique has been used to make comparative measurements of functional perfusion rates in the gastrointestinal tract of relatively undisturbed but fasted and anesthetized rats. The duodenum has the highest functional perfusion rate per unit mass of the entire digestive tract; the stomach is less than half as well perfused. The remainder of the tract to the rectosigmoid shows a progressive decrease. The small intestine shows a progressive increase in functional flow per unit mass from the pylorus to the ligament of Treitz and then a progressive decrease, most marked in the jejunum to the ileocecal valve. Blood flow values to other structures of the gastrointestinal tract are also given.
Fatty Acid Composition of Serum and Aortic Intimal Lipids in Rabbits Fed Low- and High-Cholesterol Diets
Authors: ZILVERSMIT DONALD B. , SWEELEY CHARLES C. , NEWMAN HOWARD A. I.
Published: June 2012

Lipid fractions from plasma and atheromatous lesions of cholesterol-fed rabbits were analyzed for fatty acids by gas-liquid chro matography. Pronounced differences in the fatty acid composition of plasma and arterial phospholipid fractions support the concept that these lipids are not just random deposits of the corresponding plasma lipids. Cholesterol esters of intimal lesions also differ in fatty acid composition from the plasma esters. Triglycerides ill intima and plasma showed the greatest similarity in composition.
Inotropic Effects of Purines and Pyrimidines on the Isolated Heart
Authors: BUCKLEY N. M. , TSUBOI K. K. , ZEIG N. J.
Published: June 2012

Hypoxanthine, guanine, thymine, and uracil were found to be positively inotropic for failing left ventricle preparations of the dog heart. Inosine, guanosine, thymidine, uridine, and their corresponding bases were found to be positively inotropic for failing rabbit hearts perfused with an artificial medium. Adenosine and cytidine and their corresponding bases were found to be negatively inotropic. Inosine, guanosine, uridine, and their constituent bases, and thymine were found to be positively inotropic for nonfailing rabbit hearts perfused with an artificial medium. Compounds that had hydroxyl groups in addition to one in the six position (xanthine, uric acid, 5-hydroxyuridine, barbituric acid and alloxan) had no consistently positive inotropic effects. The methylated purine, caffeine, was always positively inotropic. Compounds containing other substituents in the four or six position (6-mercaptopurine; 6-chloropurine; 2,4,6-trichloropyrimidine; 4-carboxypyrimidine) had no consistently positive inotropie effects. The carboxy derivative of uracil, orotic acid, was always a positive inotrope. Parent ring compounds such as purine, pyridine, and benzene had no consistent inotropic effects, while pyrimidine was always positively inotropic. Four consistently negative inotropic substances were found among all these compounds: xanthine, alloxan, 6-chloropurine, and 4-carboxypyrimidine. It was concluded that the constituent bases of naturally occurring nucleosides have cardiac effects similar to those of the nucleosides and that their inotropic effects are characteristic in both failing and nonfailing hearts.
Evaluation of the Pressor, Cardiac, and Renal Hemodynamic Properties of Angiotensin II in Man
Authors: FINNERTY FRANK A. , MASSARO GLORIA DECARLO , CHUPKOVICH VICTOR , TUCKMAN JOHN
Published: June 2012

These data demonstrate that in normal subjects angiotensin II is 10 times as potent as norepinephrine, which it resembles hemodynamically. An increase in the systolic pressure is associated with significant increase in diastolic pressure, increase in venous pressure, decrease in heart rate, slight decrease in cardiac output with striking increase in total peripheral resistance, decrease in renal blood flow, decreased glomerular filtration rate, increase in filtration fraction, arid slight decrease in urinary volume.

Preliminary studies of patients in shock suggest that angiotensin II is two or three times as potent as norepinephrine. Continuous administration is not associated with the development of resistance or tachyphylaxis, nor does sloughing of tissues occur when there is leakage outside the vein.
Factors Affecting Myocardial Storage and Release of Catecholamines
Authors: KAKO KYOHEI , CHRYSOHOU ATHANASIOS , BING RICHARD J.
Published: June 2012

The factors affecting myocardial storage and release of catecholamines were investi gated. The catecholainine concentration of heart muscle of normal dogs averaged 0.617 g. per Gm. of heart muscle. Ventricular tachycardia, fibrillation, and reserpine caused a slight reduction in myocardial catechol amine concentration, while nicotine resulted in a slight increase. Iproniazid was without effect. The injection of the amino acid, Dopa, and of the combinatiou of Dopa and iproni azid, resulted in a significant elevation of catecholamines in heart muscle.

In animals pretreated with Dopa and iproniazid, nicotine caused a significant in crease in myocardial catecholaniines. It is likely that stimulation of the adrenal medulla and sympathetic nerve endings by nicotine elevated catecholamine levels in blood, with subsequent storage in the heart and other organs.
Excitability and Electrical Activity of Human Myocardial Strips from the Left Atrial Appendage in Cases of Rheumatic Mitral Stenosis
Authors: VAN DAM R. T. , DURRER D.
Published: June 2012

In isolated strips of human left atrium, ob tamed during commissurotomy for rheumatic mitral stenosis, recordings of the electrical action phenomena were made and determina tiorms of the resting excital)ility amid of the ex citability cycle were carried out. Two of the four strips did not show any appreciable spontaneous electrical activity and were found to be inexcitable by applied current pulses. These strips were obtained from pa tients in whom permanent or temporary atrial fibrillation existec1 prior to operation, and in whom the left atrial appendage was grossly dilated. In the two other strips, obtained from patients with a sinus rhythm prior to opera tion and with left atrial. appendages of ap proximately normal size, determinations of strength/duration and strength/interval re quirements, together with the recorded com plexes, demonstrated the occurrence of a functional dissociation between various elements in these muscle strips, which increased during the refractory period. This functional dissociation is thought to be related to the development of connective tissue between the muscle fibers, observed by microscopic exam ination, and due to the rheumatic process. Its significance in the genesis of atrial arrhyth mias in cases of mitral stenosis is discussed. Strophanthin in a concentration of 10-8 was found to shorten the refractory period and to cause a lowering of the resting threshold for stimuli with a duration of less than 5 msec., and a rise in the threshold for larger stimuli.
Coronary Driving Pressure and Vasomotor Tonus as Determinants of Coronary Blood Flow
Authors: CROSS CECIL E. , RIEBEN P. ANDRE , SALISBURY PETER F.
Published: June 2012

A method is described that measures the contribution of coronary vasomotor tonus and extracoronary factors in the regulation of coronary blood flow. Coronary flow was measured from the bypassed right heart when the left ventricle pumped the entire systemic flow (method "A") and when a heart-lung machine generated systemic pressure (method "B"). In method "B," the mechanical activity and the oxygen consumption of the heart could be dissociated from systemic pres sure by the use of a balloon in the ventricle. Control measurements were performed in "uninjured" hearts; when a balloon was inflated to a left ventricular diastolic pressure of 15 mm. Hg or more, a state of "cardiac injury" supervened.

The arterial oxygen content was kept above 20 to 21 vol. per cent, but the cardiac oxygen consumption varied over a wide range. Whenever hemodynamic factors changed, coronary flow was a highly correlated, straight-line function of the difference between the aortic pressure and the left ventricular pressure, which we call the "coronary driving pressure." In "injured" hearts this linearity and high correlation persisted, but the slope of the regression line increased. We conclude that coronary flow is determined by the integrated difference between the propulsive force (the fluctuating pressure head at the coronary ostia) and opposing forces (intramyocardial pressure, which is known to oppose local coronary flow whenever and wherever it exceeds intravascular pressures). Cardiac oxygen consumption and coronary blood flow were not significantly related and were, therefore, coordinated by purely mechanical pressure differentials and not by changes of coronary vasomotor tonus. However, coronary vasomotor tonus decreased markedly during arterial anoxia or after various types of cardiac injury; it increased after Pitressin.
Factors Which Initiate or Influence Edema in the Isolated Dog's Heart
Authors: SALISBURY PETER F. , CROSS CECIL E. , KATSUHARA KIMIKO , RIEBEN P. ANDRE
Published: June 2012

Isolated dog hearts were perfused while time heart weight was electrically recorded. Arterialized blood was pumped into a coronary perfusion reservoir either from the femoral artery of a donor dog or from the arterial outlet of various oxygenators. The right heart was widely open. The presence of myocardial edema and the rate of fluid accumulation in heart muscle were observed from the slopes of tile weight registration and from the difference of the directly measured heart weights before and after an experiment. Blood hold-up was measured in three experiments with tagged red cells: it accounted for 15 per cent or less of the observed weight gain.

When the heart was perfused from a donor dog and was not otherwise injured, myocardial edema fluid did not accumulate unless the coronary pressure exceeded 200 mm. Hg. Myocardial edema also formed when blood was diluted with Ringer's solution or after cardiac injury; the rate of edema formation was then dependent on the coronary perfusion pressure. Edematous hearts could often be made to lose weight (i.e., edema fluid) when perfused at pressures below 100 mm.Hg. Perfusion with blood from a disposable bag oxygenator initiated inyocardial edema formation almost immediately.
Effect of Cigarette Smoking and Nicotine on Serum Free Fatty Acids
Authors: KERSHBAUM ALFRED , BELLET SAMUEL , DICKSTEIN EDWARD R. , FEINBERG LEONARD J.
Published: June 2012

The effect of cigarette smoking on serum free fatty acids (FFA) was studied in human subjects. After smoking two cigarettes there was an average maximal elevation in FFA of 351 µEq./L. This usually occurred 10 minutes after smoking and, in most instances, there was still some elevation 20 and 40 minutes after smoking. There was essentially no effect on serum cholesterol and triglyceride levels. In subjects who "chain-smoked" six cigarettes, all showed a rise in FFA during a 60-minute period, one showing a three-fold elevation. The effect of intravenous nicotine on serum FFA was studied in dogs. In 13 of 15 observations there was a rise in FFA. The mean maximal elevation of 166 µEq./L. occurred after 10 minutes of nicotine infusion. These effects are probably due to sympathetic and adrenal stimulation by nicotine. This results in a rise in circulating catecholamines which rapidly effect a mobilization of FFA from the fat stores in the body.
Hemostatic- and Fibrinolytic-Affecting Agents in Experimental Vascular Sensitization
Authors: DEMOPOULOS HARRY , COHEN SHELDON G. , SAPP THERESA M.
Published: June 2012

The effect-s of hemostatic- and fibrinolytic-affecting pharmacological agents upon the experimental model of hypersensitivity vascuhitis of the rabbit were studied. The technique of passive reversed subanaphylactic sensitization with bovine serum albumin arid gamma globulin antigen-aritibody systems was utilized in the production of lesions of pulmonary periarteritis and panarteritis, and myocarditis. Experimental procedures included attempts at inducing simultaneous (a) anticoagulant effects at the levels of action of heparin, coumaclin sodium, ethylene-diasirine tetra-acetic acid, and sodium citrate; (b) neutralization of endogenous lieparin release with protamine and hexadimetrine bromide; (3) enhancement of fibrinolytie systems with plasmin, streptokinase, and trypsiii; (d) blood "desludging" with hydroxychioroquine sulfate. Only streptokinase with anti-inflamatory properties exerted a suppressive and attenuating effect on the development of lesions of periarteritis and panarteritis.
Susceptibility of Rats with Renal Hypertension to Pyelonephritis, and Predisposition of Rats with Chronic Pyelonephritis to Hormonal Hypertension
Authors: SHAPIRO ALVIN P. , KOBERNICK JEAN L.
Published: June 2012

Renal hypertension was produced in rats by unilateral nephrectomy and constriction of the artery to the remaining kidney. Both an increased concentration of bacteria in the kidney 24 hours after inoculation of
Escherichia coli
, and an increased incidence of lesions of pyelonephritis two weeks after inoculation were noted in these hypertensive rats. Admin istration of desoxycorticosterone (DCA) and saline to rats with chronic experiniental pye lonephritis resulted in development of hyper tension of greater severity thait normal rats. Chronic pyelonephritis alone did not re sult in hypertension, nor did unilateral "fig ure-of-8" ligature in the pyelonephritic rat. Increased susceptibility to pyelonephritis in, hypertension and predisposition to hyperten sion in chronic pyelonephritis thus can ac count for a relationship between hyperten sion and pyelonephritis in the rat. If these results can be applied to the problem in man, they suggest an explanation for the clinical coincidence of the two diseases which seems more consonant with existing facts than a re lationship of direct etiology.
Cardioglobulin
Authors: LEONARD EDWARD , HAJDU STEPHEN
Published: June 2012

The plasma concentration of cardioglobulin C has been compared in hypertension, aortic stenosis, aortic insufficiency, and in a group of normal subjects. The concentration in subjects with aortic insufficiency was normal; whereas in the groups with aortic stenosis and with hypertension, the concentration was significantly increased. These findings suggest that there may be some relationship between the increased plasma concentration of cardio-globulin C and the development of increased left ventricular isometric tension in systole, which is characteristic of patients with aortic stenosis or essential hypertension.

Cardioglobulin C concentration was measured in a group of patients with congestive heart failure secondary to valvular disease, and in two groups of patients with cardiac failure secondary to myocardial disease, either of known or of unknown cause. The results showed that the cardioglobulin C concentration in congestive failure secondary to valvular disease or to muscle disease of known cause was not significantly different from normal. The 17 patients with congestive failure secondary to muscle disease of unknown cause could be divided into two populations with respect to cardioglobulin C concentration. One group had concentrations which fell in the normal range, whereas the other group had extremely low values. The findings are discussed in relation to the hypothesis that the cardioglobulin system may be essential for maintaining normal myocardial contractility in warm-blooded animals.
Physiological Observations During Induced Dyspnea
Authors: WASSERMAN ALBERT J. , PATTERSON Joux L.
Published: June 2012

In 17 iiormal subjects, dyspiiea was induced by exercise at 500 Kg.-M. per minute, with added external airway resistance. Arterial blood gas tensions and p transpulmonary I)reSsure, and pulmonary ventilation were measured iii the control period, at the onset of dyspnea, and at the disappearance of dysp ilea, which followedi cessation of exercise. Close correlation of the symptom with the functions measured was obtained through the use of hand signals by the subject to denote the onset and disappearance of ally unpleas ant sensation. The meaning of the signals was later obtained liv description. Except for a difference in time required for the devel opment of dyspnea, the results were similar whether the subject was exercised in the Su pine or in the 65-degree head-up position. In every instance, while the subjects were breath ing air, at the time of appearance of dyspnea, the arterial oxygen tension had fallen below control, levels, and at the disappearance of the symptom, the oxygen tension had returned to or near the control value. No such correla tion was obtanieci between the symptom mid the other variables measured. Subjects who did not develop dyspnea showed no fall ill arterial oxygen tension. The subjects exer (Ismg while breathing 100 per cent oxygen required longer periods for the development of dyspnea, and six of eight subjects who de veloped clysl)llea while breathing air experi enced partial Or complete relief of dyspnea despite the continuance of exercise when, un known to them, the inspired gas was switched from air to 1.00 Per cent oxygen. These resuggest that dyspnea, under the conditions of these experiments, was related to the sum- mated load of respiratory stimuli. In these experiments, the arterial oxygen tension ap pareritly was the critical variable.
Influence of Posture on Cardiac Output and Minute Ventilation During Exercise
Authors: MCGREGOR MAURICE , ADAM WILLIAM , SEKELJ PAUL
Published: June 2012

In four normal subjects, cardiac output, oxygen uptake, and ventilatory volume were compared on 8 occasions at rest and on 20 occasions during exercise in the recumbent and sitting postures. The oxygen uptake was not significantly different in the two postures either at rest or at equal external work loads. In the sitting posture during exercise, the cardiac index was approximately 12 per cent and stroke index 19 per cent lower than in the supine posture. Ventilation was signifi cantly higher because of an increase in respir atory frequency.
Ventricular Activation and the Vectorcardiogram in Bundle-Branch Blocks
Authors: SODI-PALLARES DEMETRIO , BJSTENI ABDO , TESTELLI MARIO R. , MEDRAXO GUSTAVO A.
Published: June 2012

The relationship between the ventricular activation and the vectorcarcliogram was studied in clinical aucl experimental cases of bundle-branch blocks. The observations were limited to the methods of Frank ancl Grishman, taken as representatives of the two mail1 groups of vectorcardiographic methods in use. 111 clinical cases of right or left bundle-braticll block, the curves obtained with the method of Grisli~nan showed a better correlation with the electrocarcliographic trwit~gs and with our knowledge of the sequence of the ventriv-6l ular ;wtiratioil process. I11 clogs. after the production of either right or left bundle-branch blocli, the vectorcarcliogram~s accordiilg to the methods of Frank aucl Grishman did not reveal iniportant ventricular forces which were presrn t in the vectorcardiograms calculateci from the installtaneons apparent masiinn~u potential graclients. The concept of equivalent or single clipole as representing the electrical actirity of the heart was cliscussecl. The limitations of its application to rectorcarcliogral)l~y were pointed out. Comparing the diagnostic valuc of clcctrocardiography versus vectorcarcliograpliy, the conclusion was reachecl that a distant exploration ("moving away " from the heart) will never give as much information is a. proximal esploratioil (LL~novii~g close" to the heart). The apparent superiority of Grisliman's over Frank's method was attributed to the fact that Grishmm's methocl does not adjust to the clipole concept, which is closely aclhered to in Frank's method. By adhering to the clipole concept as closely as possil,le, the ~nowments of the many activation fronts of carcliac activity are lost, ;and a situation is created which is entirely artificial according to the understanding of the activation process of the heart. A possible solution to the problem of vectorcardiograph may lie in the development of lead tensors.
Measurement of Mitral Regurgitation by IndicatorDilution Tecirniques
Authors: LEVISON WILLIAM H. , JACKSON WILLIAM D. , SHERMAN HERBERT , MCGUIIRE LOCKHART B.
Published: June 2012

ethocls f o r q u a n t i f y i n g initral regurgitation that require the measurenlent only of tlie area enclosecl by the inclicator-clilution curves offer the advantage of being computationally simpler tha11 the others. Furthermore, clistortions in the shape of t h e curve will not necessarily induce significant error in the area enclosecl by the curve. Since such methocls require sampling from t h e a t r i u m as well as from the ventricle, or proximal aorta, the?- will lw successful only if meaningful samples uf indicator concentration can he obtained from these chambers.

The cluestion remains to be arc$\\-erecl: 13 the mixing in the cardiac chambers sufficient to allow meaningful sampling in both atrium and rentricle? A review of the literature on this, subject 11s been inconclusive."-" MTe iwe not aware of any experiments in which all of the conclitions aftecting cardiac chamber mising have been controllecl without seriously disturbing normal carcliac physiology. Such ;in experiment shoulcl control the nature of injection (i.e., one or mauy successi\-e pulses). the number ancl placement of the orifices a t the tip of the injection catheter, ancl the timing of the i u j e c t i o ~ l with the carcliac cycle.

Experiments indicate t h a t the optim~um mixing conclitions exist at the beginning of ventricular filling ancl that injection should be timed to coincide with this point in tlw cycle. I t is of interest to note that, in the clye curve e x p e r i m e ~ ~ t s by Sinclair et al.Ix in whic.11 animals were used, t h e time a t which injcctions were macle was found to be unimportant. 'I'his important difference between t11c mising characteristics of the mechanical ~noclcl and an animal lieart illustrates the cliificulties cncountered in the application of moclel results ancl observations to the human heart. It seems reasonable to conjecture, ho\vever, that the \\,ell-estal~lisl~ecl mixing properties of flows through valves ancl orifiws in ripicl systems will be enhancecl in the cleformable wall situation encountered in the h r a r t . F u r t h e r experiments using the indicator-dilution technique on both normal ancl abnormal hearts are evidently requirecl t o determine the nature ancl extent of tlie clepenclence of measurement reliability on the sanipling site location.
Outflow Resistance as an Independent Determinant of Cardiac Performance
Authors: IMPERIAL ELIAS S. , LEVY MATTHEW N. , ZIESKE HARRISON
Published: June 2012

In the modified heart-lung preparation of the dog, sudden increases in outflow resistance were imposed during the diastolic interval between two beats. The changes in cardiac performance which were recorded during the first beat at higher resistance represent the response to augmented resistance per se, since there was no change in the initial length or initial tension of the ventricular myocardial fibers. Increased resistance elicited an immediate elevation of the peak aortic systolic pressure. This pressure rise was a direct function of the magnitude of the outflow resistance, and the effect was enhanced at higher left atrial pressures. Peak aortic flow and stroke volume were inversely related to the magnitude of the outflow resistance. At slight to moderate increases of resistance, stroke work was relatively unaffected; with more severe augmentations of resistance, however, stroke work varied inversely with outflow resistance. Arterial compliance played an important role in the ventricular response. For any given increase of resistance, the reductions of peak aortic flow and ventricular power were more severe when the arterial system was more rigid.

It is concluded that the limits of cardiac performance are determined by the initial conditions, such as fiber length or tension, previous activity, temperature, and nervous and humoral factors. Within these limits, however, ventricular performance is determined by the afterload, of which the outflow impedance is an integral component.
Influence of Dextran Infusion on the Pulmonary Hypertensive Effect of Concentrated Saline
Authors: READ RAYMOND C. , VICK JAMES A. , MEYER MAURICE E.
Published: June 2012

Low-molecular-weight dextran, which is known to prevent the sludging of blood cells seen in shock, has recently been reported to reduce the toxicity of concentrated radiopaque agents. Experiments have been performed to determine whether this latter effect applies to other hyperosmotic solutions. An attempt was made to delineate the mechanism involved. One ml./Kg. of 15 per cent NaCl was rapidly injected into dogs before and after infusion of 10 ml./Kg. of 15 per cent low-molecular-weight dextran. This treatment significantly reduced the usual pulmonary-hypertensive response. However, other dextran preparations, plasma, and blood were equally effective. Moreover, previous infusion of isotonic saline also conferred immunity when given at a rate sufficient to raise left-atrial pressure. Let't-atrial hypertension produced independently of changes in blood volume evoked similar amelioration. If this latter change was prevented by concurrent bleeding, none of the infusions was beneficial. Vice versa, a fall in left-atrial pressure was associated with an accentuated reaction to 15 per cent NaCl. Microscopic examination of the intact lung during protection showed that red-cell agglutination still occurred from concentrated saline, but the small vessels were dilated. It is concluded that low-molecular-weight dextran and other infusions provide prophylaxis against the pulmonary-hypertensive effects of concentrated saline by reducing the susceptibility of the lung to microembolism through the development of left-atrial hypertension.
Action of Ryanodine on Mammalian Cardiac Muscle
Authors: HAJDU STEPHEN , LEONARD EDWARD
Published: June 2012

The relationship between stimulation frequency and twitch tension was determined for isolated strips of rat right ventricle. Prolonged perfusion of the tissue in physiological saline solution results in diminished twitch tension at low rates of stimulation without alteration of contractility at high stimulation frequency. These changes, which develop over a period of several hours of perfusion, can be induced within 15 minutes by the addition of ryanodine. The addition of strophanthidin restores the twitch tension-frequency relationship of the long-perfused rat ventricle to normal. However strophanthidin has no effect on the impaired contractility of ryanodine treated ventricle ; and, conversely, the addition of ryanodine to digitalized ventricle abolishes the action of the glycoside. The effects of ryanodine can be reversed by perfusing the muscle in a solution which is deficient in either sodium or potassium.

Because of the opposing actions of ryano-dine and the cardiac glycosides, the effect of ryanodine was studied in anesthetized animals with digitoxin-induced cardiac arrhythmias. The intravenous infusion of ryanodine rapidly abolishes the ventricular arrhythmias characteristic of digitalis toxicity. However, the presence of both digitoxin and ryanodine is frequently associated with depression of sinus node activity, and the cardiac cycle is initiated by another focus, probably nodal. The effect on the sinus node may be mediated by the vagus, through a synergistic action of the two drugs, since normal sinus rhythm can be restored by the administration of atropine.
Public attitudes towards the acceptability of using drugs to treat depression and ADHD
Authors: Partridge Brad , Lucke Jayne , Hall Wayne
Published: June 2012

Objective:

This paper examines public attitudes towards the acceptability of using prescription drugs to treat depression and attention deficit hyperactivity disorder (ADHD), and whether attitudes are influenced by familiarity with the use of pharmacological treatments for these disorders.

Method:

Participants were 1265 members of the general public aged 18–101 years (50% female) participating in the Queensland Social Survey (QSS), an omnibus state-wide survey of households in the state of Queensland. The survey was administered through a CATI (computer-assisted telephone interviewing) system.

Results:

Most members of the public thought that the drug treatment of depression was acceptable (55%) but attitudes were much less positive towards the use of drugs to treat ADHD (35.6% acceptable). Regression analyses showed that respondents who knew someone who had received pharmacological treatment for depression were more likely to find it acceptable. However, participants were divided about the acceptability of drug treatment for ADHD regardless of whether they knew someone who had received drug treatment for ADHD or not. Participants with a higher level of education were more likely to find drug treatment for depression and ADHD acceptable. Participants who did not know anyone who had received drug treatment were less likely to have a definite opinion on whether it was acceptable or unacceptable.

Conclusions:

Attitudes towards the acceptability of the use of prescription drugs are more positive for depression than for ADHD. This may broadly reflect ongoing controversies in the public sphere about the potential over-diagnosis of ADHD or overmedication of children with ADHD. Members of the public who do not know anyone with depression or ADHD may need particular information from prescribers in the event that they (or their child) are diagnosed.
A historical overview of Korean public administration: discipline, education, association, international cooperation and beyond indigenization
Authors: Kim Pan Suk
Published: June 2012

Modern public administration was introduced in Korea more than half a century ago. Over the past several decades, Korea has achieved substantial economic growth as well as the significant development of a public administration system. How, and in what way, has Korean public administration as a discipline grown rapidly? This article reviews the multiple dimensions of Korean public administration: the development of public administration as a new discipline, public administration education as a new channel of management knowledge, the development of professional associations and research institutes as a promoter of research and activities, and international cooperation as a development tool and a window of opportunity. After that, prospects based on an indigenization debate and concluding remarks will follow.

Points for practitioners

Public administration played a significant role in the development of South Korea. Korean public administration programs during the developmental process fostered a new class of civil servants and public management of the government. However, post-war Korean public administration has faced a problem of indigenization as it becomes more influenced by the Western world while attempting to hold on to traditional Confucian values. Thus, Korea needs to cope with such challenges creatively as it moves forward independently from its past.
One country, two experiences: administrative reforms in China and Hong Kong
Authors: Cheung Anthony B.L.
Published: June 2012

Neither Hong Kong nor mainland China is a democracy, yet both have been active administrative reformers, having achieved significant changes but continuing to operate within systematic and institutional constraints, shaped by path-dependence. Within three decades, China has been transformed from a centrally planned economy into a thriving market economy in the name of ‘socialism with Chinese characteristics’ – a form of market authoritarianism. Hong Kong, meanwhile, had prospered as part of the ‘East Asia miracle’, and been an enthusiast of public sector reform in the ‘new public management’ fashion. Their path and logic of reform have never been entirely straightforward, displaying compromises and uneasy hybrids (more so in mainland China). Though confronted with rising political challenges to governance, both are arguably still ‘success’ types in their own right. The two reform trajectories have run in arguably totally different political contexts, but there is one similarity – administrative reforms were implemented in an authoritarian setting and had embraced a strong agenda of substituting political reforms.

Points for practitioners

This article uses the case of China and Hong Kong to illustrate administrative modernization under authoritarianism. Both have been active administrative reformers over the past three decades despite not being a democracy. Though confronted with rising political challenges to governance, both are arguably still ‘success’ types in their own right. Hong Kong, along with Singapore, is rated as high achiever by the World Bank’s global governance indicators. Despite political constraints and ideological hurdles, the scale of China’s transformation of the party-state is anything but gigantic. It was held up as exemplary of an alternative growth model, dubbed by some as the ‘Beijing Consensus’, as a counterweight to the neoliberal ‘Washington Consensus’. Their experience underscores the dynamics of governance reform under institutional and political limitations.
Luke’s Political Vision
Authors: Alexander Loveday
Published: June 2012

In order to understand Luke’s political vision, we have first to understand the complex political situation in which Acts is written. This becomes clear in the trial of Paul, where Paul stands before a Roman tribunal but addresses a dispute arising within the Jewish community. Despite his protestations of innocence under Roman law, Paul’s response embodies an inclusive political vision that is profoundly subversive of the imperial order.