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To evaluate the cardiocirculatory changes induced by acute hypoxic stress, rate corrected electro-mechanical systole (QS2)) left ventricular ejection time (LVET), and preejection period (PEP) were determined in 11 healthy males at sea level (SL) and after 2 h at a simulated altitude (HA) of 4,300 m. Recordings were made at rest and at 15 min of upright bicycle exercise at light and moderately heavy loads (40 and 75% of Vo2 max, respectively). Venous blood was withdrawn simultaneously for estimation of total plasma catecholamines (CATS). Exposure to HA produced a significant decrease in each interval at rest with differences narrowing progressively with exercise of increasing intensity. PEP/LVET ratio decreased progressively with graded exercise at SL indicating an enhancement of left ventricular performance that was directly related to the elevation in plasma CATS. Cardiac performance was augmented at rest during HA exposure, despite a normal level of CATS. However, during moderately heavy exercise at HA, when the plasma CATS were increased to twice the SL values, cardiac performance, as reflected by the PEP/LVET ratio, did not increase proportionately. It is postulated that the depressant effect of increased hypoxemia and acidosis during moderately heavy exercise in HA may override the cardiostimulatory influence of circulating CATS.

This study describes the serial responses of the systolic time intervals (STI) to submaximal and maximal supine exercise in normal subjects. Regression equations relating STI and heart rate during supine submaximal and maximal exercise are derived. It is shown that within the heart rate range of 120 to 170 beats per minute, total electromechanical systole (QS 2 ) and left ventricular ejection time (LVET) are related inversely and linearly to heart rate for both levels of exercise. At comparable heart rates, the QS 2 and LVET are greater during maximal than submaximal exercise, with differences widening significantly with increasing heart rate. This finding points out the importance of taking into account the intensity of exercise when evaluating STI responses to exercise stress in different groups. The pre-ejection period (PEP) significantly decreases from rest to the initial phase of both maximal and submaximal exercise with a subsequent tendency to plateau, indicating that a minimum PEP is reached early during exercise and that cardiovascular adaptation no longer includes additional shortening. This study also shows that STI obtained during exercise cannot be corrected for heart rate according to regression equations which were developed in resting supine subjects. Thus, there appears to be no justification for extrapolating the heart rate range of resting supine subjects to the exercise state for correcting intervals in this manner. In addition, STI measurements made during the immediate recovery period following supine exercise are significantly different from those obtained just prior to cessation of exercise. Therefore, recovery STI do not reflect the true hemodynamic changes occurring during the course of exercise. The application of the levels of exercise described in this study to the assessment of changes in STI in patients with documented or suspected cardiac dysfunction appears warranted. Alterations in left ventricular performance not evident at rest or following mild exercise might be detected employing these more strenuous exercise protocols. Using the regression equations established in this study, exercise-induced deviation in STI corrected for heart rate may now be determined with the realization that these relationships were derived from relatively young men. However, in the adult population the duration of LVET corrected for heart rate varies little with advancing age, and PEP shows only a slight increase. 34,35

Familial metaphysial dysostosis has been described as it occurred among 18 members of a family in seven generations. The roentgenologic changes were very similar to those seen in vitamin D resistant rickets. No biochemical defect could be detected. Studies of renal function with special reference to tubular reabsorption of phosphorus gave normal values. The treatment of choice is osteotomy, after epiphysial closure has occurred, to correct the pronounced bowing of the legs. Administration of vitamin D in high doses has no effect on the course of this disease.

Application of hemodialysis to dogs has been complicated by an acute reaction consisting of hypotension, bradycardia and respiratory depression followed by instability and a mortality rate of about 30 per cent. This reaction appears to be a response to homologous blood used to fill the dialyzers. Sensitization occurs in survivors, and accentuated reactions with marked hemolysis are noted on subsequent challenge. Cross matching the donor and recipient bloods has not permitted an adequate determination of compatibility under the conditions of hemodialysis. Satisfactory hemodialysis may be accomplished in dogs by using autogenous blood or blood substitutes to fill the dialyzers.

Four cases of hypertension secondary to lesions of the renal arteries are presented with comments on the history, results of physical and laboratory examinations and surgical findings. Points emphasized are as follows: 1. 1. Hypertension of renal or renal arterial origin should be suspected in the presence of: (A) acute hypertension in young patients with angiospastic ocular changes; (B) rapidly progressive symptomatic hypertension of recent onset; (C) abrupt acceleration of chronic essential hypertension; (D) a history suggestive of a recent renal vascular accident; (E) a continuous bruit over the superolateral area of the abdomen and (F) a disparity in the size and function of the kidneys on excretory urography. 2. 2. In our experience the isotope renogram has served as an excellent screening procedure for the evaluation of renal function in hypertensive patients. 3. 3. Renal arteriography is a highly desirable procedure which aids in the more complete evaluation of hypertensive patients in whom abnormalities suggestive of renal arterial disease are found on physical or urographic examination or in the isotope renograms. This is especially true when surgical intervention is planned. The vagaries of translumbar aorticorenal arteriography are legion. Retrograde aortographic technics for renal arteriography are technically more satisfactory in our experience. 4. 4. Evaluation of function of each kidney alone may on occasions prove not only of diagnostic help, but more importantly, it may provide evidence of the adequacy of function of the individual kidneys, and thus may prove decisive regarding the feasibility of surgical intervention.

Committee of the ASME Materials Processing Field: J. L. Wennberg, Therm, Inc., Chairman; B. F. von Turkovich, University of Illinois, Metal Cutting Analysis; J. R. Roubik, Kearney & Trecker Corp., Metal Cutting Practice; F. W. Boulger, Battelle Memorial Institute, Plastic Working of Metals; D. A. Farmer, Carnegie Institute of Technology, Grinding; P. A. Smith, Massachusetts Institute of Technology, Metalworking Fluids. The purpose of this review is to appraise the important contributions to the knowledge of material processing appearing in the published literature and to present a digest of this new knowledge through the Society as a contribution to the improvement of materials processing practices throughout industry.

SummarySpontaneous propagated activity was maintained at low temperatures in rabbit atria with a combination of catecholamines and low potassium in the perfusion fluid. Under these conditions, atrial activity was present at temperatures below S°C. Heretofore, spontaneous cardiac activity at such temperatures has been observed only in hibernating species.

Sodium ortho-iodohippurate (Hippuran) I 131 renography has been performed by a standardized technic in patients with renal artery stenosis, pyelonephritis, primary aldosteronism, pheochromocytoma, and renal tubular acidosis with nephrocalcinosis, as well as in patients in whom the hypertension was apparently not secondary. Fifty of 94 patients studied were found to have abnormal renograms. In patients with renal artery stenosis, all of 37 patients studied had values on the renogram that were outside the range for normal subjects. Although the renographic findings were not considered diagnostic of renal artery stenosis, certain abnormalities of the renogram were commonly observed in the presence of such lesions. When a unilateral delay in the appearance of maximal radioactivity was associated with delayed disappearance ot the medium, renal artery stenosis was frequently observed. Less pronounced differences in the function of the two kidneys were observed in patients with bilateral renal artery stenosis. A state of antidiuresis was often found helpful in the detection of less severe differences in renal function. In patients with predominantly unilateral pyelonephritis, the renographic abnormalities were qualitatively consistent with the degree of impairment of renal function. Bilateral abnormalities were observed in two patients who had bilateral parenchymal disease. The abnormalities on the renogram did not permit distinction between renovascular and renal parenchynal disease. Pyelonephritis associated with obstructive uropathy revealed findings highly suggestive of renal artery stenosis. Distinction from renovascular lesions could be determined with the aid of urographic studies. Only three of 44 patients with essential hypertension had abnormal renograms. The renograms, normal and abnormal, revealed essentially equal function of the two kidneys. The patients with abnormal renograms were not found by other technics to have evidence of secondary hypertension. The patients who were found to have pheochromocytoma and primary aldosteronism had normal isotope renograms. The patient with renal tubular acidosis and nephrocalcinosis had a bilaterally abnormal renogram and severe impairment of total renal function. The presence of a normal isotope renogram, as performed in our laboratory, is considered strong evidence against the existence of a renal or renovascular cause for secondary hypertension.

The effects of dopamine on renal function were studied in 10 patients with cirrhosis and various degrees of impairment of renal function. Dopamine caused a consistent increase in effective renal plasma flow but little change in glomerular filtration rate or sodium and water excretion. The hemodynamic change is attributed to a direct effect on the renal vasculature, resulting in reduction in both preglomerular and postglomerular resistance. Unlike other drugs, dopamine partially corrects the renal hemodynamic disturbance in cirrhosis, although its role as a therapeutic agent is limited.

This investigation describes the successful hydroponic growth of Hyoscyamus muticus L., using varying concentrations of nitrogen in Skok media. Maximum development and growth were observed between 252 and 336 p.p.m. Analysis of the flowering plants revealed constant moisture content of the total plant and its component parts at nitrogen supplies above 42 p.p.m. Fresh and dried plant weights reached a maximum at 252 p.p.m. and remained constant to 672 p.p.m. of nitrogen. Increasing the nitrate-nitrogen content of the supplied media from 0 to 252 p.p.m. resulted in an absolute increase in total alkaloid production. The flower tops contained the greatest concentration of alkaloid.

Existing chromatographic methods have been successfully adapted to the isolation and the purification of the anthraquinone derivatives of Curacao aloe. Two trihydroxy-methylanthraquinones, aloe-emodin and iso-emodin, have been separated from extracts of Curacao aloe. The use of chromatography as a quantitative method for the anthraquinone drugs has been verified and a quantitation of the total anthraquinone content of Curacao aloe is proposed.

Measurements were made of the concentration of silver in precipitation samples collected in areas of Australia where cloud seeding with silver iodide has occurred. Silver was detected in 41 of 63 ‘seeded’ samples and in three of 23 ‘unseeded’ ones. Values of concentration of the silver were between 3 × 10−11 gm ml−1. There is some evidence that silver is detected more frequently when the precipitation falls from seeded clouds which have top temperatures

The effects on the radiation pattern when N pairs of symmetrically located radiators are removed at random from a large (2N_{0}+1) -element linear array are studied as a statistical problem. It has been possible to determine the limiting bounds of the radiation pattern the probability that the main-lobe beamwidth is not widened by more than a given percentage, the probability that a certain sidelobe does not deteriorate by a specified amount and the probability that all sidelobes are below a specified level. The general analysis is valid for arrays with an arbitrary amplitude distribution which is symmetrical with respect to the center element and with an arbitrary progressive phase shift. Curves showing computed statistical data for a 201-element array with both the uniform and a cosine-squared amplitude distribution are presented.

In health, the human kidney is capable of maintaining body water, electrolyte, and acid-base equilibrium in spite of wide dietary variation. Renal disease, primary to the kidney or as part of a systemic process, is commonly accompanied by blood pressure elevation or edema, or both. Oral diuretic drugs have won general acceptance as primary therapeutic agents in mild or moderate hypertension and as part of a broader drug program for severe hypertension. Intermittent oral or parenteral diuretic therapy has greatly augmented primary therapy of edema of cardiac, hepatic, and renal origin. Attention has been called to the potential hazard of their use when impairment of renal function is severe; however, restriction is not necessary in the absence of azotemia. Frequent or excessive use of oral or parenteral diuretics is commonly associated with hypokalemic, hypochloremic alkalosis, or other electrolyte disturbances. Potassium depletion may be avoided with concurrent use of aldosterone antagonists. The use of diuretic agents in patients with impaired renal function carries distinct risks of plasma volume depletion or hypotension and further diminution of glomerular filtration. Existing electrolyte and acid-base disorders are easily aggravated. Careful sodium restriction will commonly prevent edema; however, intermittent diuretic therapy can be helpful. Hypertension can be more effectively and safely managed with sodium restriction and sympathetic nervous system inhibitors or vasodilators; however, care must be taken not to lower pressure to the point of diminishing glomerular filtration. Digitalis has proved to be not only ineffectual but also hazardous and thus contraindicated in patients with acute cardiac decompensation and renal failure; such a clinical problem constitutes an ideal indication for the use of furosemide or ethacrynic acid, which will commonly offer prompt symptomatic relief.

l, 2 with the glass electrode for the continuous measurement of the acidity of the contents of the stomach and duodenum were primarily concerned with extraneous factors that might influence such records. In these early studies concentration of acid in the stomach and duodenum was recorded under basal conditions and after stimulation. In addition, the effects of commonly used antacids were noted, although these were not reported. The rather minor pH responses to antacids that we observed have not been completely confirmed by others. 3-11 Differences in instrumentation, principally the use of electrode shields and pumps, may account for some of the differences between our findings and the results of these investiga­ tors, whose studies deserve careful review. Aspiration studies have in some instances l2 - l4 shown only small changes in pH after the administration of antacids and are more in agreement with our findings. The purpose of this paper is to describe the changes in intragastric and intra­ duodenal pH during the use of diet, antacids, and anticholinergic drugs in the treatment of patients with duodenal ulcer.

In a previous communication, Snell and we have presented our studies of serum colloid changes in hepatobiliary disease, as measured by the turbidimetric procedures of Kunkel. The present paper extends these studies to patients whose diseases are not directly related to the liver or biliary tract. On the basis of our findings in 236 blood bank donors, we have established our upper limits of normal for gamma globulin turbidity (16 units), for thymol turbidity (3.5 units), and for total serum lipids (880 mg. per 100 cc. of serum). An evaluation of normality should be carried out in each laboratory using these tests, because of possible variation inherent in the barium sulfate suspensions employed as turbidity standards. Carter and Maclagan have reported a similar investigation of "liver function" tests in extrahepatic disease, based principally on the thymol turbidity and colloidal gold tests. These workers have found a high incidence of positive values in malaria, rheumatoid arthritis, congestive heart failure, glandular fever and subacute bacterial endocarditis. The higher degree of positivity noted with the colloidal gold reaction is ascribed to the narrower dependence of this test on gamma globulin. The data of these workers are in accord with the results obtained by Kunkel with the thymol turbidity reaction. In agreement with Carter and Maclagan, we have found elevated values for gamma globulin and for thymol turbidity in several disease entities not directly related to the hepatobiliary system. It has not been shown that these reactions are specifically indicative of liver damage. Elevated values may reflect liver damage secondary to systemic toxemia, increased antibody production or variable combinations of these possibly with other factors as yet unknown. We cannot as yet describe the basic mechanisms underlying these serum colloid changes. The clinical interpretation of these tests should nevertheless consider those conditions other than hepatobiliary disease in which elevated values may be expected. With caution, the tests may be of aid in the evaluation of liver changes secondary to those conditions.

The antibacterial activities of an iodophor (Wescodyne G), a quaternary ammonium compound (Roccal), and an iodine tincture as agents for the cold disinfection of rectal catheters contaminated in vitro were determined. Following thorough cleaning with an alcoholic solution of soft soap, each of the three disinfectants tested showed satisfactory results (100% kill) in 5 min against the enteric test bacteria ( Escherichia coli and Salmonella typhosa ) as well as a test species of the genus Pseudomonas , among the bacteria most resistant to surface-active agents. An aqueous solution of Wescodyne G containing 75 ppm available iodine was used both as a wiping solution and for subsequent disinfection of rectal catheters contaminated in vivo. Total bacterial destruction was found to follow a 60-min soak preceded by the wiping procedure. Rectal catheters subjected to prolonged immersion in each of the test disinfectants were found to be essentially unaffected, retaining their initial calibrations within a permissible tolerance. Neither Roccal nor Wescodyne G solutions were found to measurably attack bare thermocouples. Alcoholic iodine 0.5% did, however, exert a deteriorating effect on bare thermocouples in a short time, as measured by change in resistance characteristics. The results of this study have led to the recommendation that Wescodyne G containing 75 ppm available iodine be used in standing operating procedures for the initial cleaning and subsequent disinfection of rectal thermocouple catheters.

A technique has been developed for generating fine particles of metaldehyde for possible use in nucleating ice in supercooled clouds. The number of particles effective as ice nuclei is 1012 gm−1 at −12C and 6×109 gm−1 at −4C. Attention is drawn to the unusual rapidity with which concentrated metaldehyde smokes coagulate. The evaporation of the particles has also been studied.

A balloon‐borne system for tracking the sun both in elevation and azimuth is described. The system weighs approximately 125 lb and is capable of ``pointing'' as much as 20 lb of payload at a predetermined position in the sky. Power requirements are 20 w. An accuracy in pointing of ±15 min of arc has been achieved. At some sacrifice in simplicity, this accuracy could perhaps be improved to ±5 min. Results of two flights, each attaining an altitude in excess of 100 000 ft, are given.

Summary Renal performances during clinical cardiopulmonary bypass, with and without hemodilution, were compared. The major difference consisted of a significantly larger rate of urine flow and a lower osmolality of urine during and immediately after cardiopulmonary bypass when hemodilution was utilized. Explanations for these phenomena were discussed. Glomerular filtration rate, effective renal plasma flow, and postoperative urine electrolyte excretion and osmolality patterns were generally similar in both groups of patients. It was concluded that the increased production of urine associated with hemodilution perfusion might well protect renal-tubular integrity during stressful situations, such as intracardiac surgery.

One of us (Somogyi)1 has shown that in diabetic patients the continued overdosage of insulin, i. e., the administration of quantities sufficient to cause hypoglycemias, gradually diminishes the carbohydrate tolerance of the patient and aggravates the diabetic condition. In this paper we call attention to the fact that insulin when administered to nondiabetic individuals, exerts a similar effect.This observation was made on nondiabetic tuberculous patients, who were treated with insulin with the purpose of inducing an increase in their body weight. The procedure in this work differed from others described in the literature in 2 respects. In the first place, the amount of insulin used was very small. In 2 cases only 10 units were given daily, injected in 5-unit doses before the noon and evening meals, while the remaining patients received at the beginning 10, and subsequently 20 units daily, always administered in 2 equal doses. In the second place, the duration of the treatment in this experiment was much ...

In sensitized albino guinea pigs it was not possible to demonstrate therapeutic activity for jewelweed in poison ivy dermatitis after the outward manifestations became apparent. Neither was it possible to exhibit activity in limiting the biologic activity of poison ivy when poison ivy extracts and jewelweed juice were combined in vitro, or on the skin. This was attributable to a lesser degree of sensitivity in guinea pigs than in man and the greater amounts of ivy toxin necessary to elicit dermatitis exceeded the neutralizing powers of even concentrated preparations of jewelweed. In human subjects jewelweed was of no value in treating experimentally established dermatitis. Jewelweed juice or concentrated solutions of jewelweed enzymes were capable of inactivating more dilute poison ivy extracts when mixed in vitro and tested on human subjects under controlled conditions.

In 149 cases, blood pressure response to glucagon test did not exceed 20/10 mm Hg more than the response in the cold pressor test control and was considered negative. Plasma catecholamine level increases may be seen in 95% of patients without pheochromocytomas. Among six patients with pheochromocytomas, urinary metanephrine levels were of diagnostic importance in two with isolated pheochromocytoma and in one with the multiple endocrine neoplasia of type 2 (MEN-type 2). Urinary metanephrine determinations yielded false-negative results in three patients with MEN-type 2, while vanilmandelic acid level was normal in one and nephrotomograms were positive in two of these three. These results suggest that the early diagnosis of pheochromocytoma in patients with MEN-type 2 may be difficult and may require multiple biochemical and roentgenographic investigations.

On 247 of the 1,711 scintiscans (15%), the appearance of renal or urinary tract areas differed sufficiently from normal to merit mention in interpretation. For 162 patients (195 surveys), the abnormalities noted were classified as "minor." For 39 patients (52 surveys), the abnormalities noted were classified as "major"--that is, confirmed by other means or considered of major importance to diagnosis and management. Of these, 9 were filling defects (2 each were renal cell carcinoma, simple cyst, and polycystic disease; 3 were a mass of undetermined nature) and 30 were unilateral or bilateral urinary tract obstruction indicated by hydroureter and massive retention in renal area(s). These obstructive manifestations were associated with primary pelvic or prostatic malignancy or extension of malignant disease; in nine patients, progression or remission of obstruction was noted on sequential imaging. These changes were compatible with changes in clinical status and may afford an added means of following response to therapy in appropriate patients.

Serial changes in serum magnesium (Mg2+) were assessed in unacclimatized males during treadmill exercise in a hot (49 degrees/27 degrees C, dry/wet bulb) environment. Eight subjects walked at 5.6 km/h on a 0% grade, and at 90 min of exercise had a mean heart rate of increase of 70 plus or minus 5 (S.E.) beats/min, rise in rectal temperature of 2.1 degrees plus or minus 0.1 degrees C, and a weight loss of 2.07 plus or minus 0.10 kg. There was a significant (p less than 0.01) decrease in mean serum Mg2+ concentration (control: 1.87 plus or minus 0.06 mEq/I; 45 min: 1.81 plus or minus 0.07; 90 min: 1.72 plus or minus 0.08). The Mg2+ concentration in sweat samples collected over 90 min of work in the heat averaged 0.28 mEq/I (range 0.13 to 0.45). Thus, in normal man, exercise in an hot, dry environment resulted in a fall in serum magnesium which was not wholly explicable on the basis of sweat loss of this ion.

This study examined the hypothesis that prevention of hypocapnia and alkalosis would ameliorate the symptoms of acute mountain sickness (AMS). Five subjects were exposed to simulated high altitude for 4 d with 3.8% CO2 added to the chamber to maintain normocapnia. Four other subjects were exposed for 4 d to hypobaric hypoxia without CO2 supplementation, and became hypocapnic. Barometric pressure was lower in the group with added CO2 so that alveolar oxygen tensions (55-60 mm Hg) would not be different. The severity of symptoms was clearly greater in normocapnic than in hypocapnic subjects. Thus, prevention of hypocapnia did not alleviate AMS symptoms. The efficacy of CO2 addition in reducing symptoms, as reported by earlier workers, was probably the result of induced hyperventilation and partial relief of hypoxia. Indeed, in the present study with two comparably hypoxic groups, CO2 addition augmented the sysptoms, possibly by causing increased cerebral vasodiladation and spinal fluid pressure.

The rate and extent of return of renal function and its maintenance after initial improvement and factors influencing renal recovery were studied in 186 patients with acute renal failure. ...

Renal performance of seven patients undergoing replacement of the aortic valve was investigated. The initial portion of cardiopulmonary bypass was characterized by low arterial blood pressure and anuria. With a subsequent rise in arterial pressure during bypass, urine flow suddenly increased in five patients. In two patients urine flow did not resume until immediately after cardiopulmonary bypass. The high rate of urine flow at these times is thought to be partially due to a glucose-induced osmotic diuresis. The glomerular filtration rate (inulin clearance) and the effective renal plasma flow (PAH clearance) fell with induction of anesthesia and opening of the chest, but there was no further drop in these functions as a result of total body perfusion. Urine osmolality fell significantly during and immediately after cardiopulmonary bypass. The changes in urine osmolality are thought to be due in part to the osmotic diuresis and in part to a temporary reduction in the renal medullary hyperosmolality secondary to hemodynamic changes. All of the alterations in renal function were reversible in the patients studied.

A technique for measuring effective renal plasma flow based on a single injection of sodium iodohippurate I 131 was compared with para-aminohippuric acid clearance determined simultaneously in 25 patients. On the average, the clearance by the single-injection technique was about 19 ml (5%) less than that by the standard procedure. The results indicate that there is a good correlation between the methods. It is suggested that further study with this simpler technique may prove it to be a reliable substitute for the more cumbersome standard method.