[Effect of flight factors on changes in blood coagulation and anticoagulation indices in crew members].

A total of 105 flight qualified crewmembers, aged 20 to 40, were taken under observation. Coagulographic and thromboelastographic parameters of the venous blood were studied. The most significant changes (an increase in the coagulation time as related to the time of plasma recalcification, a decrease of the plasma tolerance to heparin, R, K, R plus K, a decrease in the coagulation index Si with respect to the thromboelastogram, a significant increase in the fibrinolytic activity and the heparin number) were noted postflight in commanders, pilots and navigators. Less significant variations of the coagulographic parameters were observed in other crewmembers. The above changes (an increase in endogenous heparin, an acceleration of the fibrinolytic activity) can be regarded as the protective-adaptive reaction of the anticoagulatory system aimed at reducing hypercoagulation during the emotional stress-effect of the flight.


Experimental evaluation of heat and moisture transfer in metal dog cage environments.

Dog cages with solid and expanded metal flooring were tested while unoccupied, occupied by a 10-kg adult male beagle, and occupied by simulated loads to represent a beagle and a greyhound. Cage performances were evaluated with no direct coupling between the room air supply and the cage, and with mechanical coupling of 50% and 100% of the room air supplied directly to the cage. At each of these conditions, the room was maintained at approximately 24 degrees C and 45% relative humidity with room air exchange rates of 5, 10, and 15 changes per hr. Results indicated significant differences existed in dry-bulb and dew-point temperatures between the cage and the room. These differences, together with significant vertical gradients of air velocity and dry-bulb and dew-point temperatures within the cage were shown to be affected by room air exchange rate, cage flooring, type of coupling, and cage load.


Methods for obtaining neonates of known age from the Virginia opossum (Didelphis marsupialis virginiana).

Postlactational estrus occurred in the opossum 6-17 da (mean 10.08 +/- 3.2da) after sucklings were removed from the pouch 1-60 da postpartum. This estrus occurred somewhat earlier in females whose young were removed later than 24 hr postpartum, rather than within the first 24 hr. Thirteen litters (37% conception) resulted from 35 initial attempts at breeding during postlactational estrus. Three of 5 females conceived when litters were removed twice in succession. The tendency forindividual females to bear large or small litters was sustained regardless of conventional or postlactational breeding. Continual rebreeding of the opossum after removal of nursing young may increase the yield of known age neonates for experimental purposes.


The parasitic ecology of the rodent mite Myobia musculi. II. Genetic factors.

Mice of 4 strains, C57BL/6J, CD2F1(BALB/cCum female times DBA/2Cum male), BRVR/SrCr and BSVS/SrCr, were monospecifically infested with an equal number of Myobia musculi. A single skin field (7mm diam) in the dorsal midline slightly posterior to the eyes was used for periodic observation of mite populations. Mite counts were made by direct microscopic examination of the skin field at 10-da intervals. Data were obtained on mice thus infested and observed for 130 da. Between-strain comparisons differed significantly in the number of Myobia maintained in all cases except between BRVR and BSVS strains. Factors bearing on heritable differences in susceptibility were discussed.


[Psychophysiological characteristics of the performance of a suited operator].

The performance of a suited operator was studied. The experiments were carried out in a trainer consisting of a cockpit and electronic model of the plane attitude realized by an Electron analogue computer. The experiments showed that a special suit may decrease the performance. The main cause for that is that under positive pressure the influx of afferent signals impoverishes due to a reduction of proprioceptive feedback. This disturbs the interaction of the optic and motor analyzers. In order to increase the performance of a suited pilot, it is necessary to build the construction maintaining the optic-proprioceptive relation.


[Experiment with a physiologically active culture of Chlorella on "Soiuz-9" spacecraft].

A physiologically-active culture of chlorella was for the first time exhibited on board the "Soyuz-9" spacecraft. The use of a special four-socket container made it possible to investigate in one experiment the effect of the factors of a space flight on the cells of algae developing in illumination during 1, 6 and 14 days. Besides that the effect of the flight conditions was studied on the culture of chlorells. Insignificant change in sensitivity of the cells to the effect of the flight factors depending upon the duration of their exposure in the active condition is shown.


Reproductive performance of a laboratory colony of the deermouse, Peromyscus maniculatus gambelii.

During a 23-mo period approximately 600 litters and 2,500 offspring were produced in a laboratory colony established with wild-trapped deermice (Peromyscus maniculatus gambelii). The incidence of pregnancy and size of litters increased with domestication. Average litter size was 4.3 for all litters and 4.1 and 4.7 for litters born to wild-trapped and first generation females, respectively. Litter size increased up to the seventh sequential pregnancy for both wild-caught and first-generation females and then tapered off. In all litters more males were born than females. The departure from a 1:1 ratio was significant for the combined data and for litters of first-generation females, but not for litters of wild-caught females.


[Change in the asymmetry of paired functions in pilots during flight].

The flight activity of a pilot brings about peculiar changes in the asymmetry of physiological functions whose pattern depends to a large extent on the initial state of asymmetry. An inflight change in the functional state and the interaction of paired structures of the cerebral hemispheres results in a reduction of the predominance of the leading hand in pilots with distinct asymmetry preflight and in an increase of opposite asymmetric fluctuations in pilots with insignificant asymmetry preflight.


Lateral hermaphroditism in a C3H mouse.

A spontaneous case of true lateral hermaphroditism was observed in one of approximately 1000 necropsies of 12-wk-old female C3Hf-Wg mice (a substrain of C3H/He). Both the right ovary and abdominal left testis were functional as evidenced by the presence of oocytes in graffian follicles and spermatocytes maturing on sertoli cells. Both gonads communicated, the ovary via an oviduct and normal right uterine horn and the testis via an epididymus and vas deferens, with a vagina which ended in a blind pouch and was filled with squamous debris.


[Effect on humans and animals of multiple exposures to rarefied atmospheres].

In order to study the chronic form of decompression disease, clinical and physiological examinations of 38 test subjects were carried out. They participated in 133 chamber experiments and were exposed to an altitude of 11,000--12,000 m for 2--3 to 20--24 hours after desaturation of different duration. Besides, histological and histochemical examinations of organs and tissues of 3 dogs were performed. During 70, 110 and 140 days the dogs were exposed 20, 33 and 35 times to an altitude of 12,000 m for 2--2.5 hours without preliminary desaturation. No persistent pathological changes were found in the animal or human body.


Mycotic encephalitis in weanling rats.

An outbreak of mycotic encephalitis occurred in rats 15-31 da old. Eight of 170 rats born within a 2-wk period had histologically proven mycotic encephalitis with the characteristics of phycomycosis (mucormycosis). No mycotic lesions were seen in the lungs or organs other than the brain.


[Human tolerance to Coriolis acceleration during exertion of different muscle groups].

The effect of an arbitrary loading of different muscle groups (shoulder, back, legs) and motor acts on the tolerance to Coriolis accelerations was investigated in 140 experiments in which 40 test subjects participated. The accelerations were cumulated and simulated by the Bryanov scheme. Muscle tension was accompanied by a less expressed vestibulo-vegetative reaction and shortening of the recovery period after the development of motion sickness symptoms. The greatest changes were observed during the performance of complex motor acts and tension of shoulder muscles. Possible mechanisms of these effects are discussed.


An apparatus for anesthetizing small laboratory animals.

A simple apparatus was designed for simultaneous general anesthesia of a number of small laboratory animals with spontaneous respiration. Anesthesia is consistent over many hr. The apparatus consists of an oxygen tank and vaporizer, a glass distribution bottle, and a non-return circuit of separate inspiratory and expiratory valves for each animal. The equipment is inexpensive to construct and can be rapidly adjusted for exact control of gas flow and anesthetic depth.


Automated weighing procedure for toxicological studies on small animals, using a minicomputer.

A compact system was designed for weighing procedures in toxicological studies on small animals that integrated 4 basic functions: data acquistion, record keeping, statistical analysis, and report preparation. An electric balance, a minicomputer, and a typewriter were incorporated into the system. Elimination of clerical work and accelerated flow of information between planning, operation, and evaluation of experiments were found to be the main advantages.


Hematology of neonatal Japanese quail.

The hematologic development of Japanese quail was studied as a function of time through the first 49 hr post-hatching. Packed cell volumes, hemoglobin levels, erythrocyte and leukocyte numbers, as well as differential percentages of lymphocytes, heterophils, basophils, eosinophils, and monocytes were determined. Additionally, the mean corpuscular volumes, mean corpuscular hemoglobins, and mean corpuscular hemoglobin concentrations were calculated. Of particular interest are the increasing mean corpuscular volume and the increasing number of erythrocytes which were observed as the birds aged. Between the 13th and 19th hr after hatching, an almost 2-fold increase in the erythrocyte number was detected with a concomitant decrease in the mean corpuscular volume. These findings indicate that the state of the hematologic system in quail is highly dependent on the stage of post-embryonic maturation.


Versatile, protective jacket for chronically instrumented dogs.

A versatile nylon jacket was designed for mixed-breed dogs to permit easy access to cardiac instrumentation and to protect the leads when not in use.


Studies of the capillary basal lamina.  I. Ultrastructure of the red body of the eel swimbladder.

The rete mirabile of the eel swimbladder is a vascular organ in which arterial andvenous capillaries alternate in regular fashion.  The endothelium of the arterial capillaries is high, whereas that of the  venous capillaries is thin and fenestrated.  Endothelial cells and pericytes are the only cells found in the rete.  A tubular systemin the arterial endothelial cells is connected with the organelles.  The basal laminaeof both capillaries are similiar to those of mammalian capillaries of the same type.  They present three layers of different electron density and have a high fibrillar pattern.A fine fibrillar material and dense fibrils appear in the cisternae of the rough endoplasmic reticulum and in large vacuoles of endothelial cells and pericytes: these cells areapparently involved in the synthesis of their lamina.  Since the rete mirable ofthe eel swimbladder is a pure vascular preparation, it is most useful for the study of themorphology, the permeability, and the metabolism of the endothelial cells and for the analysis of the chemical structure of their basil laminae.


Studies of the capillary basal lamina.  II. Preparation, chemical composition, andmetobolic properties.

Large amounts of basal laminae material can be extracted by sonic disruption from the capillary tissue of the rete mirabile of the eel swimbladder.  The extracted basil laminae material has the same fibrillar pattern as that found in the intact tissue.  Thechemical composition is similiar to that of other basil laminae isolated from tissues inmammals, with high content of glycine, proline, hydroxyproline, lysine, and hydroxylysine.  The mono- and disaccharide units linked to the hydroxylysine are also present.  Of all the pathways of glucose utilization, the 'C-glucose incorporation into the basallamina glycoproteins is the most sensitive to the medium glucose concentration.  The glucosyltransferase activity seems stimulated to a plateau value of saturation when the medium glucose concentration is raised from 5 to 20 mm.  The 'C-labeled amino acid incorporation into the basal laminae glycoproteins is not affected bythe medium glucose concentration.  The results obtained in this study allow for a hypothesis which links the biochemical, morphologic, and functional properties of various typesof basal laminae in normal and hyperglycemic conditions.


Interactions between collagen chains and fiber formation.

The temperature-dependent dissociation of neutral salt-soluble collagen into its component chains was measured in 0.6-1.6 M urea solutions at pH 7.3. The temperature-dependent association of the same radioactively labeled collagen into fibers was measured in 0-0.4 M urea solutions, pH 7.3. The effect of urea on the temperature, Tm(G), for half dissociation into chains was small, and the value extrapolated to zero urea concentration was 39 degrees C. In contrast, the effect of urea on the temperature, Tm(F), for half association into fibers was large, and the value at zero urea concentration was 30 degrees C. We conclude that while body temperature provides excellent conditions for the matching of collagen chains to form molecules, the conditions are not optimal for the formation of highly ordered fibers. The large effects of 0.1 M urea suggest that other factors in vivo may help to destabilize mismatched molecular association during fiber growth. Alternately this might be facilitated by parts of the extension peptides of procollagen.


Assembly of the tail of bacteriophage T4.

The protein products of at least 21 phage genes are needed for the formation of the tail of bacteriophage T4. Cells infected with amber mutants defective in these genes are blocked in the assembly process. By characterizing the intermediate structures and unassembled proteins accumulating in mutant-infected cells, we have been able to delineate most of the gene-controlled steps in tail assembly. Both the organized structures and unassembled proteins serve as precursors for in vitro tail assembly. We review here studies on the initiation, polymerization, and termination of the tail tube and contractile sheath and the genetic control of these processes. These studies make clear the importance of the baseplate; if baseplate formation is blocked (by mutation) the tube and sheath subunits remain essentially unaggregated, in the form of soluble subunits. Seventeen of the 21 tail genes specify proteins involved in baseplate assembly. The genes map contiguously in two separate clusters, one of nine genes and the other of eight genes. Recent studies show that the hexagonal baseplate is the end-product of two independent subassembly pathways. The proteins of the first gene cluster interact to form a structure which probably represents one-sixth of the outer radius. The products of the other gene cluster interact to form the central part of the baseplate. Most of the phage tail precursor proteins appear to be synthesized in a nonaggregating form; they are converted to a reactive form upon incorporation into preformed substrate complexes, without proteolytic cleavage. Thus reactive sited are limited to growing structures.


The formation of filamentous structures from iodinated neurotubules.

The porcine neurotubule and its basic subunit were found to be modified in vitro by iodination of amino acids (principally tyrosine) using lactoperoxidase. Iodide ion, H2O2, or lactoperoxidase singly or in any pairwise combination had virtually no effect on neurotubules. However, when all three reagents were present, permitting covalent iodination, it was found that at 0.1 iodotyrosines per tubulin dimer the microtubules unravel to form structures which morphologically resemble strands of protofilaments twisted or wound around each other. These abnormal tubules are stable at room temperature and 4 degrees C. Both monomers of tubulin are labeled to approximately the same extent. Iodinated tubulin (0.1 iodotyrosines/dimer) is unable to assemble in vitro under normal assembly conditions. Heavily iodinated microtubules (8 iodines per tubulin dimer) are similar in morphology to the slightly iodinated structures.


Radioiodination of the envelope proteins of Newcastle disease virus.

Lactoperoxidase-catalyzed iodination selectively labels the two glycoproteins (VP1 and VP2) of Newcastle disease virus. The low-molecular-weight, nonglycosylated major viral protein, VP6, was not iodinated in the intact virus but was iodinated in disrupted virions, suggesting a localization on the inner, rather than the outer, envelope surface. Studies on the distribution of virion proteins labeled with 125-I and 3-H-isoleucine between detergent-soluble and detergent-insoluble fractions show that the virion proteins VP4, VP5, and VP6 are solubilized to a much lesser extent than are VP1 and VP2.


Hemocyanin - antibody labeling of phodopsin in mouse retina for a scanning electron microscope study.

To reveal the presence of rhodopsin on the surface of the mouse retina, a scanning electron microscope study of the immunolabeling of rhodopsin was attempted. The glutaraldehyde-fixed mouse retina was treated first with rabbit antibodies specific against bovine rhodopsin and then with hemocyanin-labeled goat antibodies specific against rabbit antibody. The distribution of hemocyanin label on mouse retina and the technique used for labeling are discussed.


Oxidation of lipids and membranes I: in vitro formation of peroxidative lipid polymers.

Fluorescent polymers were obtained by oxidizing partly emulsified linolenic acid with different oxidants. The speed of formation of polymers differed for the various oxidants, and the difference was not a simple function of the oxidation potential. The speed of polymerization also depended on the nature of the emulsion. The presence of egg albumen in the emulsion enhanced polymer formation with all oxidants. When the oxidants used are arranged in the order of decreasing speed of polymer formation, the order is different in the presence of albumen from what it is in the absence of albumen. With different oxidation catalysts most antioxidants and amino acids tested enhanced polymerization. In oxidation with ferric ions, with K-dichromate, and without added oxidants the only antioxidants which delayed polymerization were "inhibitors." "Retarders" enhanced polymerization. With KMnO4 slight delay was caused by some retarders. The findings indicate that not only oxidation catalysts, but also proteins, amino acids, and antioxidants enhance polymerization. The possibility is suggested that in animal cells lipid pigment formation might represent a mechanism for neutralizing free radicals.


Oxidation of lipids and membranes II: Effects of oxidants on cerebral white matter homogenates.

Bovine cerebral white matter homogenates were oxidized by various oxidizing solutions of equal molarity and subsequently extracted with water. Most of the oxidants tested (K-dichromate, FeCL3, H2O2, O2, and chloroperbenzoic, ascorbic, performic, and periodic acids) rendered the various myelin constituents less extractable than the constituents of unoxidized control homogenates. KMnO4, and to a lesser degree hemoglobin, rendered myelin constituents more extractable with water than those of the control homogenates. The findings indicate that most of the oxidants produced stabilization of the lamellar pattern, probably through cross-linking and polymerization. KMnO4 and hemoglobin caused labilization and breakdown of the membranous structure. Proof that stabilization of membranes is caused by some oxidants and that fragmentation occurs by the action of KMnO4 and hemoglobin was obtained by the light scattering technique and by electron microscopy of the oxidized homogenates. Evidence obtained indicated that formation of hydrophobic end groups during oxidation favors polymerization, while prevalence of hydrophilic groups is associated with fragmentation.


Secretion analysis: secretin testing in pancreatic cancer.

Modern testing of pancreatic function and the diagnosis of pancreatic disease is facilitated by the addition of augmented stimulus to the standard stimulus used in secretin testing. The combined standard-augmented secretin test protocol enables not only diagnosis using the classical patterns of secretion (qualitative and quantitative defects), but also permits delineation of secretory capacity. In the abnormal patient, the augmented test increases the defect in the characteristic diagnostic parameter. Thus, there is fixation of flow in pancreatic cancer and fixation of bicarbonate in pancreatic inflammation.


Unusual lesions of the parotid gland.

Ten unusual cases of parotid tumors are added to the literature from a series of 318 consecutive parotidectomies. These 10 cases are: 3 branchial cleft cysts; a lipoma; a lymphangioma; a hemangiopericytoma; a Boeck sarcoid; a metastasizing basal cell carcinoma; a lymphoma of the parotid; and a metastatic adenocarcinoma from the left breast to the right parotid. The lymphoma, Case 1, is also an example of some other cranial nerve taking over the function of the facial nerve when it is destroyed in early childhood. Though most tumors of the parotid gland are of the mixed type, many suprising findings are possible. The pathology report may be the first clue to a hidden systemic disease.


Staging carcinoma of the penis.

Presently there are six clinical staging systems in use for carcinoma of the penis. We propose a method which compares these systems by means of a check list type of format. With the aid of this device, any penile carcinoma can readily be staged in terms of all six systems. Advantages of multiple system staging include comparing series of patients which have been discussed only in terms of a single staging system and selecting the appropriate therapeutic modality in terms of the stage of disease.


Pelvic neoplasms causing pain.

The following is a discussion of dyspareunia and its role as an aid to diagnosing pelvic neoplasms. The great majority of cases of dysparenia are psychosomatic in origin, and in a large proportion of the remaining cases, painful coitus is an indicator of benign problems. Nevertheless, painful coitus is a symptom which requires careful pelvic examination to rule out the possibility of pelvic neoplasm and to discover treatable causes of dyspareunia.


Intraoperative delineation of ischemic and scarred myocardium by localized detection of potassium-42 in dogs.

The range of emission from 42-K was shown, in a model experiment, to be suited to scanning with a detector positioned on the surface of the heart after intravenous injection of the isotope. This finding was verified by comparing surface counts with the activity of transmural samples of underlying tissue. Two groups of dogs were studied. In Group A, dogs with left ventricular scars produced by the agar injection technique were given 42-K 24 hours before study. In Group B, normal dogs were given 42-K immediately after ligation of a coronary artery branch. In Group A, localized counting clearly delineated scar from surrounding normal myocardium, and the values were 39 per cent of normal. When more 42-K was given, low flow in scar was indicated by markedly reduced uptake. In Group B, counts over the acutely ischemic area were as low as 20 per cent of normal. Thus, the possibility of differentiating scarred from normal myocardium was shown. Moreover, the results suggest that ischemic but still viable areas that may be suitable for revascularization can be assessed by application of the method.


Isolated replacement of the aortic valve with the Starr-Edwards prosthesis. A 9 year review.

A 9 year review of patients who underwent replacement of the aortic valve with the Starr-Edwards prosthesis indicates that the operative mortality rate for aortic valve replacement continues to decline. Thromboembolic complications have been markedly lessened in newer model valves. Surgical therapy is no longer seriously questioned as the appropriate management for symptomatic aortic valvular disease. The large majority of patients who survive surgery can expect to be rehabilitated to a highly functional existence, with longevity not unlike that of the general population. The Starr-Edwards prosthesis is a very satisfactory prosthesis for replacement of the aortic valve.


Influence of primary closure of the pericardium after open-heart surgery on the frequency of tamponade, postcardiotomy syndrome, and pulmonary complications.

Experiences with primary closure of the pericardium in a series of 100 patients undergoing open-heart operations are described. The pericardium was kept under tension during the operation to minimize shrinkage and permit closure at the end of the procedure. In 28 patients one pleural space was opened for drainage, whereas in 72 patients intra- and extrapericardial sumps alone were used for drainage. Measurements of sump drainage revealed that most postoperative bleeding originates from outside the pericardium. There were no instances of cardiac tamponade although 19 patients lost more than 1 L. of blood after operation and 5 required reoperation for hemorrhage. Transpleural drainage tubes were shown to be ineffective and in addition were associated with a fourfold increase in postcardiotomy syndrome and a significantly greater frequency of pleural effusion and atelectasis when compared to the use of mediastinal sump drainage alone. We have concluded that closing the pericardium and using mediastinal sump drainage minimizes the risk of cardiac tamponade and allows early localization of the site of postoperative bledding. Another advantage of pericardial closure and drainage is that postoperative adhesions and postcardiotomy syndrome will be less significant. As a consequence the danger of injuring the heart in a subsequent operation is lessened.


Pre- and postoperative manometric studies in diffuse esophageal spasm.

Since January, 1972, the authors have operated upon 4 patients with idiopathic diffuse exophageal spasm. Clinical details and barium studies are included. Extramucosal myotomy extending from the gastric fundus to the aortic arch was done in each case. Pre- and postoperative manometric studies were carried out in all. After operation in each patient the dysphagia and substernal pain disappeared and in 3 patients radiological patterns changed. The myotomy was associated with marked fall of contractile wave pressures in the body of esophagus. The basal pressures of the esophageal body elevated, in 2 cases fell after the myotomy; in 2 with normal preoperative pressure it remained unchanged. At the lower esophageal sphincter the resting and yield pressures remained similar to the preoperative readings but the myotomy produced a disappearance of the relaxation and contraction pressure. The authors conclude that with myotomy they cannot correct the nature of the functional disorder but, by reducing the amplitude of the waves and lowering the resting pressure if elevated, they can relieve the patient's symptoms.


Protection from lung damage by blood filtration during deep hypothermia in puppies.

Ten puppies underwent deep hypothermia with surface cooling and bypass cooling. They were subjected to circulatory arrest for 30 minutes and then were rewarmed by means of bypass. There were 5 control puppies and 5 for which a Swank filter was placed in the arterial perfusion line. All puppies had some degree of lung damage, but it was more severe in those in which perfused blood was not filtered. The damage involved the lung vessels, interstitial tissue, and alveoli. Platelet-fibrin aggregates and margination and sequestration of leukocytes appeared to be important pathological findings. Apparently, the Swank blood filter protects the lung by removing leukocytes and damaged platelets from the circulation.


Metastatic carcinoma (endometrial adenoacanthoma) to the trachea. Report of a successful resection and primary anastomosis.

The first case report of an adenoacanthoma of the endometrium with metastasis to the trachea is presented. Successful resection with primary anastomosis was done, followed by external radiotherapy. The patient has been followed for 3 years to date with no evidence of recurrence. A brief discussion of this tumor is given.


Failure of Beal mitral valve prosthesis. Clinical and radiographic features.

This report presents a case of severe dysfunction of an improved Model 104 Beall valve secondary to disc wear. This type of valve failure may be extremely difficult to detect by auscultation, echocardiography, or fluoroscopic examination. Prosthesis failure with resulting mitral insufficiency should be considered in any patient with a Teflon disc Beall mitral valve in whom there is unexplained clinical deterioration.


Effects of systemic-pulmonary shunts on regional myocardial blood flow in experimental pulmonary stenosis.

The pulmonary artery of anesthetized dogs was constricted until right ventricular failure occurred (decreased cardiac output and aortic blood pressure; elevated right ventricular end-diastolic pressure). Coronary blood flow distribution was measured by means of an electromagnetic flowmeter and radioactive microspheres. With moderate levels of pulmonary stenosis (right ventricular pressure to 60 per cent of systemic pressure), right ventricular coronary flow increased (30 per cent, p smaller than 0.01) despite a significant fall in right ventricular driving pressure (aorto-right atrial pressure). Right ventricular failure occurred when right ventricular coronary flow did not increase sufficiently to meet raised oxygen requirements. Opening a pulmonary-systemic shunt during right ventricular failure increased pulmonary blood flow but lowered coronary driving pressure further, as blood was diverted into the lungs through the low-resistance fistula. Consequently, right ventricular coronary flow fell 50 per cent (p smaller than 0.01) and right ventricular failure with pulmonary stenosis resulted in a 362 per cent (p smaller than 0.01) increase in right coronary flow plus improved cardiac output. We made the following conclusions: (1) Right ventricular failure with pulmonary stenosis and intact ventricular septum is due to inadequate right ventricular blood flow to meet raised oxygen demands; (2) opening a pulmonary-systemic shunt may potentiate this failure and exaggerate ischemia by lowering coronary driving pressure and reducing right ventricular coronary flow.


In vivo study of a new radioisotope-powered cardiac pacer.

A new radioisotopic pulse generator has been developed. It is 6 cm. long, 4.7 cm. high, 1.92 cm. wide, and weighs 61 Gm. (2 oz.). It is the smallest pulse generator made and has a life expectancy of over 20 years. The circuit is a conventional ventricular-inhibited (V.V.I.) type. In vitro testing has passed all Atomic Energy Commission requirements. The present study is concerned with in vivo testing of the complete pacemaker system, by means of both myocardial and endocranial electrodes, in 20 dogs with and without induced heart block. Extensive testing for electromagnetic compatability was carried out on 1 animal with induced heart block and a special, fast-rate pulse generator. Based on studies to date, the Atomic Energy Commission has issued a license for limited clinical trial which has already begun at the collaborating institutions.


Congenital mitral stenosis.

This report presents a 15 year review of the surgical treatment of 9 patients with congenital mitral stenosis seen at the Columbus Children's Hospital. The over-all mortality rate was 45 per cent. Seven patients had associated lesions, mostly coarctation of the aorta and patent ductus arteriosus. In the planning of the operative procedure, distal obstructive lesions of the left heart should generally be relieved first. The mitral valve should be explored with the use of cardiopulmonary bypass and the anatomic type of the valve determined. Type I valves will often respond to open valvulotomy, whereas Type II and III valves must be replaced.


The hemostatic mechanism after open-heart surgery. I. Studies on plasma coagulation factors and fibrinolysis in 512 patients after extracorporeal circulation.

Blood coagulation screening profiles were performed in 512 patients who underwent open-heart surgery with extracorporeal circulation. Severe coagulation disorders were found in 29 (5.6 per cent) patients. The most common abnormalities were low one-stage prothrombin time (PT) activities and impaired whole blood clot retractions. In the majority of patients the discrepancy between low PT's and normal or only slightly depressed factor II, V, VII, and X activities was explained by the presence of an inhibitor of the extrinsic system. Eight patients demonstrated the heparin rebound phenomenon but only 1 bled excessively. The pattern of severe hepatic dysfunction was found in 4 and severe depression of vitamin K-dependent factors due to oral anticoagulants in 2. Two had disseminated intravascular coagulation. Seventeen patients with normal coagulation screening profiles bled excessively postoperatively. Of these, 2 had moderate thrombocytopenia associated with a marked platelet functional abnormality. Revision of the wound in 13 revealed a surgical hemostatic defect and in 2 the cause of bleeding could not be determined.


A new roentgenographic finding in acute traumatic rupture of the aorta.

A new chest roentgenographic finding for acute traumatic rupture of the thoracic aorta is described. The film showed separation of calcified intima from the adventitia by a hematoma.


Oxygen consumption of the normal and failing heart during left heart bypass.

In order to determine whether myocardial oxygen consumption (MOC) is decreased during left heart bypass (LHB), two groups of 6 dogs each were subjected to 2 hours of heparinless LHB. Group 2 differed from Group 1 in that cardiogenic shock was induced by temporary coronary artery occlusion prior to LHB. In Group 1 animals (normal dogs), MOC decreased significantly during the surgical preparation but did not change appreciably during subsequent LHB. Upon completion of LHB, MOC increased slightly in all animals. This increase in MOC was insignificant, however, when adjusted to changes in mean aortic blood pressure (MAP). A highly positive linear correlation between MOC and MAP was noted regardless of whether the animals were on or off bypass. In Group 2 animals, MOC was markedly decreased after the iduction of cardiogenic shock but gradually increased during the 2 hours of LHB. Upon completion of bypass, MOC of the damaged heart increased to a remarkable degree, but not to initial control levels. However, the linear correlation between MOC and MAP, noted before the induction of cardiogenic shock, disappeared after shock and was not restored after 2 hours of apparently successful bypass. We have concluded that MOC is decreased surgical stress and is further decreased by temporary coronary artery occlusion. MOC is not, however, reduced by nearly total or total LHB in normal hearts. MOC is markedly decreased by cardiac damage but gradually increases in damaged hearts by the use of LHB.


Refinement in application of total artificial heart, with improvement in survival and histopathological findings.

Recent improvements in total artificial heart (TAH) experiments have changed the pathological findings as well as the concept of the TAH. In the past 3 years, 67 experiments were performed in our laboratory. This study concerns the 11 calves operated upon most recently. Histopathological findings in the lungs, kidneys, livers and spleens of these animals were greatly improved over findings from previously studied animals. Disseminated intravascular coagulation (DIC) syndrome has been seen in only 1 calf. These improvements can be attributed to the following factors: (1) Improved management of the lumg during surgery has essentially eliminated pulmonary insufficiency;(2) liver damage has been successfully prevented by the discovery of the relationship between high right atrial pressure and anemia; (3) careful aseptic surgical procedures and optimal prophylactic use of antibiotics and anticoagulants have minimized the incidence of infection and clot formation.


Successful emergency replacement of the ascending aorta and aortic and mitral valves in the Marfan syndrome.

A 37-year-old man with the Marfan syndrome and chronic mitral regurgitation suffered an acute dissecting aneurysm of the ascending aorta with aortic regurgitation. Emergency replacement of the mitral valve, aortic valve, and ascending aorta was carried out, and the patient made an uneventful recovery. He is doing well 18 months after surgery. This is the first reported case of survival from such a procedure in the face of acute dissection with Marfan's syndrome. Indications for elective surgery are discussed and the uncertainties about the prognosis outlined. Continued reporting of the results and follow-up data are necessary for final assessment of the surgical treatment of the cardiovascular manifestations of this disease.


Obstruction of superior vena cava after the Mustard procedure for transposition of the great arteries. Conservative management of chylothorax.

Chylothorax may be produced by superior vena cava (SVC) obstruction, a recognized complication of the Mustard operation for trasposition of the great arteries. The chylothorax may be reduced by keeping the subject in the upright position. Conservative management is an alternative to repeat operation. This syndrome must be recognized, as it can be confused with congestive heart failure. Severe chylothorax may develop insidiously because of progressive SVC obstruction after the immediate postoperative period.


Congenital lung malformations: a unified concept and a case report.

A left upper lobectomy in a 5-month-old infant revealed a specimen whose tissue, both grossly and microscopically, was characteristic of intr- and extrapulmonary swquestration, bronchial atresia, and adenomatoid cystic malformation. This case may be considered the missing link between the various congenital lung malformations, for it illustrates their interrelationship or their common origin. Atresia or malformation of the main bronchus seems to be the defect shared by all these anomalies. A similar bronchial abnormality probably is responsible for congenital lobar emphysema and isolated congenital lung cysts.


Take-down of cava-pulmonary artery anastomosis (Gleen) during repair of congenital cardiac malformations: report of 5 cases.

The dismantling of previously made anastomses between the superior vena cava and right pulmonary artery (Glenn shunts) and reconstruction of superior vena cava-right artial continuity have been accomplished in 5 patients at the time of intracardiac repair of congenital heart defects. All patients survived the hospitalization period, but 2 died late postoperatively of causes apparently not related to the cava-atrial reconstruction. Experience with these 5 patients and the intraoperative techniques employed are presented.


A new approach to total repair of transposition of the great vessels: a technique for atrial autotransplantation.

We have devised a new operative procedure called atrial autotransplantation for transposition of the great vessels and applied it in 7 cases. Results were satisfactory except for one death. The bais of this technique was the experiment, using 70 dogs, in which the relationship of separation of the atrial wall and atrial septum to the development of arrhythmia was studied. It was found that reservation of the upper one sixth of the right atrial wall and the upper one third of the left atrial wall developed almost no significant arrhythmia with slow rate. By this concept and method, the left and right atria are almost completely separated, and a complete intraventricular and intra-atrial repair is made in a satisfactory operative field. Since there is no surgical intervention in the ventricular wall, postoperative cardiac function can be satisfactorily maintained. With this procedure intr-atrial conversion was performed in four cases and intraventricular conversion in three cases-the former for type I of uncomplicated transposition and type III of combined pulmonary stenosis, with or without VSD, and the latter for type II of combined large VSD. Only one patient with intraventricular conversion died of low cardiac output syndrome, probably due to incomplete relief of combined pulmonary stenosis.


The hemostatic mechanism after open-heart surgery. II. Frequency of abnormal platelet functions during and after extracorporeal circulation.

In a prospective study of 13 patients undergoing open-heart surgery with extracorporeal circulation, marked qualitative platelet function defects were observed in addition to the usually occurring drop of the thrombocyte count. At the end of bypass, the following test results were significantly abnormal: concentration of fibrinogen and of circulating fibrin degradation products, platelet count, platelet adhesiveness to glass beads, and platelet aggregation induced by low and high doses of ADP. One to 2 hours after neutralization of heparin with protamine sulfate all abnormal test results improved, but the template bleeding time was markedly prolonged in 10 patients. There was no correlation between length of bypass and platelet fall and between concentration of circulating fibrin degradation products and extent of platelet dysfunction. An apparent correlation was found between the length of the postoperative bleeding time and the number of units of blood transfued during surgery. The results of this study suggest that dilution of the patient's own platelets by nonviable platelets contained in 3-day-old transfused ACD blood and the production of a refractory state of the patient's circulating platelets to ADP induced aggregation played a significant role in the development of platelet function abnormalities during extracorporeal circulation.


Myocardial ultrastructure and function during progressive early ischemia in the intact heart.

Regional contraction of ischemic anterior and normal lateral left ventricular myocardium was measured with isometric force gauges after 5, 10, 15, and 20 minutes of anterior descending coronary artery occlusion-each followed by 10 minutes of reperfusion. Multiple myocardial biopsies of both regions were taken at these same intervals and examined by electron microscopic techniques. Mean contraction of the ischemic area fell significantly in 15 to 30 seconds and returned to an average of 68, 51, 40, and 28 per cent, respectively, after 5, 10, 15, and 20 minutes of ischemia. Simultaneously, focal morphologic changes were detected after 5 and 10 minutes, were more clear and widespread at 15 minutes, and diffuse and unequivocal at 20 minutes, when return of local contraction was minimal. The changes of myocardial morphology in the ischemic area as seen by electron microscopy were: reduced content of glycogen granules and mitochondrial changes. The latter began to appear at 5 minutes and consisted of swelling, disruption of cristae, and reduction of matrix. This study indicates a qualitative correlation between ultrastructural changes in regionally ischemic myocardium and diminished regional function in the intact heart. At 5 and 10 minutes the mitochondrial changes were focal, requiring multiple samples, while at 15 and 20 minutes they became more widespread, making the occasional sample more representative.


A study of the electroencephalogram during surgery with deep hypothermia and circulatory arrest in infants.

Seveteen infants (2 1/2 to 28 months old) were continuously monitored by six-channel electroencephalography (EEG) during the entire surgical procedure of open-heart repair. They were subjected to surface hypothermia supplemented by cold extracorporeal circulation (ECC) down to an average esophageal temperature of 21 degrees C., to cardiac arrest of 40 minutes average (range 19 to 62 minutes), and to ECC rewarming. Survival time of the EEG was correlated to esophageal temperature at the time of arrest. EEG reappeared an average of 26 minutes (5.30 to 50) after the strat of rewarming ECC and became strictly continuous after 44 minutes. Reappearance latency was well correlated with the duration of arrest. Potential normalization was oberved in 13 infants, but true normalization was observed in only 2 infants during the 90 to 120 minute period after ECC. By judging the EEG and by comparing this series with two previous series of moderate and deeper hypothermia in older patients, we concluded that the immediate tolerance of the brain to deep hypothermia and circulatory arrest seems no different in infants and in older patients.


Failure of transfusion of autologous whole blood to reduce banked-blood requirements in open-heart surgical patients.

Although transfusion of autologous blood by the method described would seem to be a safe and proctical means of reducing banked-blood requirements for open-heart operations, our experience indicates that the amount of blood needed to be added to the pump oxygenator more than negates the value in reducing intraoperative blood requirements. In fact, autologously transfused patients used more blood than did control subjects. Platelet and fresh-frozen plasma administration was not significantly different for the autologous transfusion or control group.


Effect of pacemaker-induced arrhythmias on coronary blood velocity in conscious man.

With the use of the Doppler ultrasonic catheter telemetry system, phasic left coronary blood velocity was measured in 34 conscious subjects during transvenous pacemaker insertion and right ventricular endocardial pacing. Ventricular premature depolarizations and ventricular tachycardia, occurring as consequences of pacing catheter manipulation and competitive rhythms, reduced peak coronary blood velocity by approximately one halft. These findings provide insight into the genesis of sudden death associated with pacemaker insertion, competitive or repetitive arrhythmias, and pacemaker "runaway."


Surgical correction of a rare variant of cor triatriatum.

Cor triatratum is a rare congenital malformation. Problems in diagnosis and surgery arise due to associated anomalies such as atrial septal defects and anomalous pulmonary venous drainage. A 21-year-old man proved to have a rare variant of cor triatiatum in which both the upper and lower compartments of the left atrium communicated with the right atrium through two separate atrial septal defects. In addition, he had anomalous drainage of the right superior pulmonary vein into the superior vena cava. Intracardiac repair was undertaken successfully.


Carcinoma of the esophagus and cardia: diagnostic evaluation in 113 cases.

Fiberoptic endoscopy with directed biopsy and brush cytology was used to diagnose 73 patients with squamous carcinoma of the esophagus and 40 adenocarcinomas of the gastric fundus invading the lower esophagus. Over-all accuracy of histologic diagnosis in the esophagus was 95.8 per cent and in the cardia, 97.5 per cent. Multiple biopsies (6 to 8) and brush cytology complemented one another in providing a high index of reliable histologic diagnoses. There were no complications. Endoscopy with the fiberoptic scope as now performed is well tolerated and accurate. It appears to be the most reliable means of diagnosis in cancer of the esophagus and cardia and should be performed routinely in all patients with symptoms referable to the esophagus.


Peritoneal fluid in the rabbit: permeability of the mesothelium to proteins, lipoproteins and acid hydrolases.

The peritoneal fluid in rabbits fed a normal and a cholesterol added diet was analysed for a wide variety of macromolecules of different size, viz albumin, alpha-, beta- and gamma-globulins, high density lipoprotein and lipoproteins of Sf0-12, Sf12-20 and Sf greater than 20 and three acid hydrolases, N-acetyl-beta-d-glucosaminidase, acid phosphatase and beta-glucuronidase.  The composition of the lipoproteins and the concentrations of each substance were compared with corresponding values in plasma, hepatic lymph, thoraic duct lymph and leg lymph.  The results indicate that the large lipoproteins of the thoraic duct lymph derived from the intestinal mucosa do not normally enter the peritoneal cavity probably because they do not mix with the subserous tissue fluid, that the macromolecular composition of peritoneal fluid resemble that of leg lymph, that the peritoneal mesothelium is freely permeable to these macromolecules and that the main plasma: peritoneal fluid barrier resides in the blood capillary membrane of the various subserous tissues.


Contribution to the solution of the question of lympho-venous anastomoses in heart of dog.

The efferent lymphatic vessels of the heart were ligated in 35 dogs and afterwards the systems of lymphatic and blood vessels were filled with various media by injection.  Twelve of these dogs were sacrificed 30 min. after ligature and the remaining 23 dogs were left to survive for two to 132 days.  After acute ligature of lymph routes, no lymphatic anastomoses could be found.  In the protracted experiment, lympho-lymphatic anastomoses had developed between the interrupted trunks and very thin ones at the sites of adhesions between the epicardium and pericardium by the seventh to 14th day.  In five out of 23 dogs, lymphovenous anastomoses of a calibre of 40-60 mum. were found between the seventh and 28th day after ligature.  After one month, these LVA could no longer be found.  Both forms of anastomoses, i.e. lympho-lymphatic and lymphovenous, may be present at the same time.  The mutual relationship between these forms was discussed in the paper.


The role of lymphography in "apparently localized" prostatic carcinoma.

The preliminary results of an ongoing protocol which is attempting to determine the incidence of lymph node metastasis in unselected patients with previously untreated "apparently localized" carcinoma of the prostate are briefly presented.  All patients have disease confined to the prostate gland or periprostatic bed, without evidence of metastasis by standard clinical, laboratory, and radiographic (excluding lymphography) tests.  Following lymphography, a "staging laparotomy" is performed which permits histologic documentation of lymph node metastais and provides data for the evaluation of lymphographic accuracy.


Lipoprotein profiles in adult nephrotics.

Lipoproteins and lipoprotein profiles were determined in 96 adult nephrotic patients. The serum cholesterol-serum albumin, serum triglycerides-serum albumin and 24-hour urine protein loss-serum albumin values were all significantly inversely correlated. The serum triglycerides and serum cholesterol levels were not significantly lower in the group of lupus nephrotic patients compared to the nonlupus nephrotics. All lipoprotein types except type I were observed. The lipoprotein types fell into three nearly equal groups--IIa, IIb, and V. Type IV, the most common lipoprotein abnormality in uremic patients, was distinctly uncommon.


Low-incidence cesarean section: 12-year experience.

At the Mayo Clinic from 1962 through 1973, 592 cesarean sections were done among 16,181 deliveries (3.7%); 48% were primary procedures, and 52% were performed because of previous cesarean delivery.  Regional anesthesia using epidural block recently has replaced a balanced general anesthesia as the anesthesia of choice for cesarean sections.  Although the low cervical operation was performed in most cases, the classic operation and cesarean hysterectomy were used when indicated.  In our series, prophylactic antibiotic therapy failed to decrease the maternal morbidity, and the most frequent causes of neonatal mortality were prematurity and respiratory problems.


Evaluation of renal and urinary tract abnormalities noted on scintiscans: a retrospective study of 1,711 radioisotope skeletal surveys performed in an 18-month period.

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.


Monte Carlo calculations on polypeptide chains. VIII. Distribution functions for the end-to-end distance and radius of gyration for hard-sphere models of randomly coiling poly(glycine) and poly(L-alanine).

A Monte Carlo study of the distribution functions for the end-to-end distance and radius of gyration for hard-sphere models of poly(glycine) and poly(L-alanine) random coils has been conducted in the chain-length range n = 3 to 100 monomer units for both unperturbed chains and chains perturbed by long-range interactions (excluded volume effects). The distribution functions for the radius of gyration in all cases have been very precisely calculated, those for the perturbed end-to-end distance less precisely, and those for the unperturbed end-to-end distance least precisely. Empirical distribution functions of the form W(p) = ap-b exp(-cp-d) for the reduced end-to-end distance p = r/"r-2"-one-half and a similar form for the reduced radius of gyration could be least-squares fit to the Monte Carlo data. The expansion factors alpha-r and alpha-s were calculated vs. chain length and were used to test various versions of the two-parameter theory of the excluded volume effect. To be consistent with the chain-length dependence of alpha-r and alpha-s as determined by the Monte Carlo calculations, each of these theories required two different binary cluster integrals, a beta-r based on alpha-r and a beta-s based on alpha-s, both of which were strongly chain-length dependent. Both of these results suggest that the two-parameter theory is not applicable to the models used in this study. It was also found that, except for very short chain lengths, plots of ln alphs-r vs. ln n were linear, and thus that alpha-r could be estimated for long chain lengths. Comparison of these estimates with the experimental data on four polypeptide chains in one-earth solvents that the hard-sphere models used in this study yield expansion factors that do not seriously overestimate the magnitude of the excluded volume effect.


Identification of the conduction system in corrected transposition and common ventricle at operation.

The high incidence of surgically induced heart block in patients with levotransposition of the great arteries is now better understood because of recent anatomic demonstration of an unusual anterior location of the atrioventricular specialized conducting tissue.  The two cases reported herein proved electrophysiologic confirmation of this previously described anatomy.  The specialized conducting bundle was easily and consistently identified and then avoided in successful surgical correction in one patient with common ventricle, type A-3, and in another with corrected transposition, large ventricular septal defect, and valvular pulmonary stenosis.  Electrophysiologic identification of the atrioventricular conduction tissue at the time of operation may decrease the incidence of heart block and offers additional optimism for successful correction of levotransposition complexes.


Dielectric dispersion of polypeptide solutions. II. Helix-coil transition of poly(epsilon-carbobenzoxy-L-lysine) in m-cresol.

Dielectric dispersion measurements were made on dilute solutions of poly(epsilon-carbobenzoxy-L-lysine) in m-cresol; this system underwent a very sharp thermal helix-coil transition of inverse type around 30 degrees. Mean-square dipole moments "mu-2" and mean rotational relaxation times t were obtained as functions of molecular weight and helical fraction fN. It was found that "mu-2"-one-half varied almost linearly with fN-one-half over a substantial portion of the transition. The relaxation times corrected for solvent viscosity and temperature changed only slightly with fN except in the region of small fN, while, at fixed fN, they displayed molecular weight dependence characteristic of rod-like molecules. These results can be explained if the transition is assumed to proceed almost in all-or-none fashion. This assumption is consistent with the previous finding from statistical thermodynamic analyses that the transition of the system PCBL-m-cresol is highly cooperative, with standard deviation of population one-half being 0.0025 to 0.0027, where standard deviation of population is the cooperativity parameter. Application of Nagai's theory of "mu-2" for interrupted helices yielded the result that standard deviation of population-one-half was in the range 0.001 to 0.005 and the monomeric dipole moment in the helical conformation was 5.4 to 6.2 D.


The clinical and pathologic correlation of fat embolism syndrome.

The fat embolism syndrome is a well-defined clinical entity that can usually be recognized in patients who have long-bone fractures. Cerebral symptoms of restlessness, confusion, stupor, and coma correlate with the autopsy findings of fat in the brain, but the amount of fat or amount of petechial hemorrhage cannot be quantitated with the severity of the cerebral symptoms. There is a correlation between the clinical manifestations of dyspnea and tachypnea and the autopsy findings in the lungs, which are heavy from edema and alveolar hemorrhage; however, we cannot correlate the degree of pathologic change in the lung, including lung weights, with the severity of findings clinically.


Copper metabolism after biliary fistula, obstruction, or sham operation in rats.

Intravenously administered carrier-free 67Cu appeared rapidly in the bile of rats with a recently created biliary fistula; maximal excretion occurred within the first 2 hours.  However, if the biliary fistula had been created 3 or 4 days before injection of the 67Cu, only one-fourth to one-half as much of the isotope appeared in the bile.  There also was a small decrease in stable biliary copper.  When rats with biliary fistula were compared with rats with permanent biliary obstruction, over a period of 6 weeks, both exhibited a marked increase in plasma copper and an equally pronounced increase in the rho-phenylenediamine oxidase activity of plasma but no increase in hepatic copper.  Peaks in blood were reached within 2 weeks and then slowly diminished. Sham-operated rats had parallel, but much lower, copper and enzyme changes.  Correlations between these rat studies and the copper retention of Wilson's disease and of primary biliary cirrhosis are suggested.


Echocardiographic features of straddling tricuspid valve.

Echocardiographic features were studied in four patients with straddling tricuspid valve, a rare and complex cardiac anomaly that may defy diagnosis by angiocardiography. The most significant echocardiographic feature was a septal echo recorded at a depth corresponding to the midportion of the tricuspid valve with one of the tricuspid valve leaflets opening posterior to the ventricular septum in diastole. Certain of the features, which appear to be distinctive for this anomaly, have not previously been described.


The cellulose microfibril as an imperfect array of elementary fibrils.

Cellulose microfibrils are viewed as imperfect array of elementary fibrils. We have investigated the possible defects in Valonia cellulose microfibrils, which are such that the microfibrils can be broken into elementary fibrils by deformation, but are not sufficient to allow for a small angle maximum corresponding to the elementary fibril dimension. The microfibril has been constructed by convolution of th elementary fibril with a two dimensional point lattice. Defects have been incorporated in the microfibril, first by introduction of gaps between the elementary fibrils. These regular gaps were then replaced by a statistical distribution of the elementary fibrils about the lattice points, modeled by Hosemann distortions of the first type. The cylindrically averaged transforms of such structures show that significant distortions can be incorporated within the microfibril without producing large scale changes in the equatorial intensity distribution. Larger distortions are necessary before a small angle maximum corresponding to the 35 A elementary fibril is predicted, by which stage the wide angle x-ray pattern is unacceptable.


Configurational statistics of polynucleotide chains. A single virtual bond treatment.

A simplified single virtual bond scheme has been developed for the calculation of mean-square unperturbed dimensions in polynucleotide chains. As a consequence of the structural rigidity of the sugar residues in the chain, it is possible to represent the six chemical bonds comprising the chain backbone repeating unit by a single virtual bond (connecting successive phosphorus atoms). The mutual orientation of a pair of adjoining virtual bonds is determined by the angles of rotation about the phosphodiester bonds adjoining intervening phosphorus atoms and is independent of the orientation of all other virtual bonds in the chain. Computed values of chain dimensions based on the single virtual bond scheme are comparable to those calculated previously using a two virtual bond model which permits rotational flexibility in the sugar moieties of the chain.


Wilson's disease (hepatolenticular degeneration) of late adult onset: report of case.

Wilson's disease usually has its onset in childhood, adolescence, or early adulthood. The clinical picture of hepatic dysfunction without dysfunction of the central nervous system is more typical of the disease in the child or the adolescent than in the adult. We are presenting the case of a man whose age at onset of the disease was 55 years and who had the hepatic complications of Wilson's disease without clinical evidence of disease of the central nervous system. All patients with chronic hepatitis (chronic active liver disease) or cirrhosis of unknown etiology should be screened for the possibility of Wilson's disease. This screening should include slit-lamp biomicroscopy for Kayser-Fleischer rings, determination of serum ceruloplasmin concentration, and measurement of 24-hour urinary excretion of copper. If doubt exists concerning the diagnosis, either a radiocopper kinetic study, using 64Cu or 67Cu, or, if the patient's condition permits, a liver biopsy with measurement of hepatic copper concentration should be done. The rubeanic stain of hepatic tissue for copper is unreliable in making or excluding the diagnosis of Wilson's disease.


The use of therapeutic soft contact lenses in corneal disease.

Soft contact lenses are being applied as a therapeutic device in various diseases and postoperative conditions of the cornea. Ten cases illustrate several of the clinical conditions in which lenses of approved types may be used, with adjunctive medication in some instances.


Breast restoration after mastectomy for cancer.

The clinical problems encountered in the reconstruction of breasts of patients who have undergone mastectomy for cancer are presented. The indications and contraindications for reconstruction of the breast are arbitrarily defined. Various methods are available to reconstruct the breast. We favor implantation of a preformed silicone prosthesis under the skin and subcutaneous tissue overlying either the pectoralis major muscle or the chest wall. The advantages of this procedure outweigh those of other methods. Seven cases are presented to illustrate our experience in this rehabilitative procedure. It is suggested that breast reconstruction should be offered to a much higher proportion of patients undergoing mastectomy for breast cancer.


Sertoli cell tumor: case report with ultrastructural findings.

In this case of Sertoli cell tumor of the testis, no laboratory or clinical evidence of hormonal imbalance was present. The histologic and ultrastructure characteristic of the tumor agreed closely with previous reports on these rare tumors of the gonadal stroma.


Congenital H-type tracheoesophageal fistula complicated by achalasia in an adult: report of a case.

A young adult with a congenital H-type tracheoesophageal fistula complicated by achalasia of the esophagus presented with complaints consistent with existing long-standing asthma. Only on direct questioning were esophageal aspects elicited. This combination of conditions proved difficult to diagnose even though suspected. Esophageal x-ray in the prone-oblique position proved valuable in the diagnosis and localization of the fistula. Correction of the obstruction of achalasia preceded fistula repair. Fistula repair involved sleeve resection of the trachea, with tracheal anastomosis after closure of the esophageal defect.


A distinctive clinical EEG profile in herpes simplex encephalitis.

Two patients with herpes simplex encephalitis had clinical courses consisting of an acute febrile illness with early onset of seizures and rapidly progressive neurologic signs evolving to coma and death within 3 weeks. The electroencephalograms of both patients were similar and showed widespread, periodic, stereotyped sharp-and-slow-wave complexes occurring bilaterally over both hemispheres, as well as transient episodes of electrographic seizure activity occurring unilaterally, with suppression of the periodic activity on that side. Although the electroencephalographic findings are not pathognomonic, when associated with an acute encephalitic process, they would suggest the diagnosis of herpes simplex encephalitis.


Supra-his alternate-beat Wenckebach dysrhythmia.

Alternate-beat Wenckebach, an uncommon dysrhythmia, usually is attributed to block within the His bundle or bundle branches (or in both). A patient with features of the "sick sinus" syndrome demonstrated A-V nodal (supra-His) alternate-beat Wenckebach during atrial pacing and His bundle electrocardiography. Electrophysiologic mechanisms are proposed.


Serum dopamine beta-hydroxylase activity following subarachnoid hemorrhage in man.

Serum dopamine beta-hydroxylase activity was followed in seven patients who had experienced primary subarachnoid hemorrhage resulting from a ruptured intracranial aneurysm. This preliminary study suggested that dopamine beta-hydroxylase levels were initially elevated following subarachnoid hemorrhage, after which they progressively declined during the first week post hemorrhage. After a minimum was reached, the activity rose again to a stable level two to three weeks post hemorrhage.


Low molecular weight DNA polymerase: decreased activity in spleens of old Balb/c mice.

The DNA polymerase activities in the spleens of young adult (3-8 months) and senescent (24-30 months) female BALB/c mice have been examined. Comparisons were made by direct assay of activated DNA-dependent and (rA)n-(dT)n-dependent activities in extracts from cytoplasmic and neclear fractions and also by sucrose gradient sedimentation analysis of the two major forms of DNA polymerase activity was equivalent in the spleens of young and old BALB/c mice. The low molecular weight DNA polymerase activity was decreased in the spleens of old BALB/c mice. This decreased activity was reflected most markedly in the nuclear fraction of the spleens. Mixing experiments did not indicate the presence of inhibitors in the nuclear extract from the old mouse spleens. Stepwise extractions of isolated nuclei with increasing NaCl concentrations showed consistent results without revealing any difference in extractability of the low molecular weight DNA polymerase from the old mouse chromatin. Isolated low molecular weight DNA polymerase preparations from the young and old BALB/c mouse spleens are similar in chromatographic migration, sucrose gradient sedimentation, heat lability in vitro and Km of substrates. The low molecular weight DNA polymerase activity was not found to decline in livers and kidneys of 24 to 30-month-old BALB/c mice, nor in spleens of 30 to 34-month-old BC3F1 mice.


Metabolism of deoxycholic acid in man.

The metabolism of [24-14C] deoxycholic acid was studied in humans with an intact enterohepatic circulation. Two metabolites were identified in hydrolysed duodenal bile: 3alpha-hydroxy-12-oxo-5beta-cholanoic and 3beta,12alpha-dihydroxy-5beta-cholanoic acids. Quantitative analysis of one sample showed the amounts of these compounds to be about 2 and 0.5%, respectively, of the amount of deoxycholic acid. A small percentage of deoxycholic acid, less than 3%, was found in a fraction having the chromatographic property of conjugated bile acid sulphates. About 15% of the identified metabolites were found in this fraction, which also contained more than 50% of the biliary lithocholate and 90% of the biliary 3beta-hydroxy-5-cholenoate.


Cholesterol exchange between the red blood cells and plasma of young and old rats.

The exchange of unesterified cholesterol between plasma and red blood cells of young (1.5 month) and old (1-2 years) rats was studied using [3H]-cholesterol as label. Using labeled plasma and unlabeled red blood cells, no equilibration of specific activity of unesterified cholesterol with the specific activity of cholesterol of red blood cells occurred in either young or old rats. Using labeled red blood cells and unlabeled plasma, equilibration of radioactivity of cholesterol was observed in both young and old rats. However, a more rapid exchange of free cholesterol was observed when labeled old red blood cells were incubated with unlabeled plasma. This apparent paradox may be explained by the existence of a larger, more readily exchangeable pool of free cholesterol in red blood cells of old rats than of young rats. Red blood cells and plasma of old rats contained significantly more free cholesterol than those of young rats but phospholipid levels were comparable.


Effect of L-DOPA on endogenous histamine metabolism.

To estimate the effect of long-term administration of L-3,4-dihydroxyphenylalanine (L-Dopa) on methylation of compounds not formed from it, the urinary excretion of histamine and its methylated metabolites was studied in rats and guinea pigs fed L-Dopa in their diets and in patients with Parkinson's disease being treated with L-Dopa. In the guinea pigs, but not in the rats, L-Dopa administration decreases excretion of histamine and of its methylated metabolites, methylhistamine and 1-methylimidazole-4-acetic acid. Because excretion of 1-methylimidazole-5-acetic acid, which comes from the diet and is not a metabolite of histamine, was unaffected by the L-Dopa treatment, the decreases were due to a specific effect of L-Dopa on histamine metabolism. When compared to normal control subjects, patients with Parkinson's disease excreted less histamine and methylhistamine, both before and during treatment with L-Dopa. Administration of the peripheral aromatic L-amino acid decarboxylase inhibitor, L-alpha-methyldopa hydrazine (MK 486), decreased urinary excretion of histamine markedly. Neither L-Dopa nor MK 486 appeared to influence excretion of the imidazoleacetic acids in the patients. The results suggest that L-Dopa may decrease histamine formation or release in some species but that it does not influence histamine methylation.


Aging of human fibroblasts in vitro: surface features and behavior of aging WI 38 cells.

WI 38 cells at various in vitro ages and an SV 40 virus tranformed variant were examined by (3)H thymidine autoradiography, time lapse cinematography and scanning electron microscopy. Among normal WI 38 cells it was shown that htere was a good correlation between cellular morphology, behavior, and the ability to incorporate (3)H thymidine. Small, elongate spindle-shaped cells were usually both active incorporators of (3)H thymidine, as determined autoradiographically, and dividers as determined by time lapse cinematography; larger, more spread out cells tended to be nondividers. The proportion of large, nondividing cells increased with increasing in vitro age and was correlated with changes in cell surface and behavior. Transformed WI 38 cells exhibited no such changes as a function of age. Results support the thesis that in vitro aging reflects the inability of individual cells to undertake DNA synthesis and to complete division, but nondividers continue to enlarge and unusual sizes and shapes are attained. Associated with these aging changes were conspicuous alterations in cellular curface features and behavior.


Effect of the dietary manganese level on tissue manganese, iron, copper and zinc concentrations in female rats and their fetuses.

In order to study the effect of dietary manganese on the content of manganese, iron, copper and zinc in maternal and fetal tissues, six diets with different levels of manganese (4, 24, 54, 154, 504 and 1004 mg Mn/kg dry diet) were fed to Sprague-Dawley female rats from the time of weaning. The animals were mated and the offspring collected by cesarean section at day 21 of pregnancy. Non-pregnant female rats served as respective reference groups. Concentrations of copper as well as manganese were higher in the livers of pregnant rats with the highest manganese intake, whereas in non-pregnant animals the dietary manganese level had no appreciable effect on manganese or copper concentrations in the liver. On the other hand, the iron content of the livers of both pregnant and non-pregnant female rats fell as the manganese level of the diet increased. The hemoglobin values of dams on the highest levels of dietary manganese were also slightly reduced. The manganese content was highest in the offspring of dams given the largest amounts of manganese. The manganese level in the maternal diet had the opposite effect on the fetal iron concentration, and the zinc content of fetuses of dams on the highest dietary manganese level was slightly elevated. No gross malformations or bone structure anomalies could be observed in the fetuses, and the manganese intake of the dams was not found to have influenced essentially the fetal weights and the dry matter and ash contents.


State regulation of health care costs.

State regulation of health care costs has been increasing at the same time as criticism of governmental regulation in other sectors of the economy has been increasing. The authors examine major system elements necessary to effect cost control in health care, present normative models of value preferences which underlie alternative state cost control systems, and indicate control foci and intervention strategies for state government under the alternative models. The authors conclude that state governments should assume responsibility for controlling health care costs. Presently, state regulatory agencies should emphasize development of adequate information systems, strengthening of state regulatory capability, and implementation of experimental reimbursement programs rather than comprehensive and detailed rate setting.


Chick embryo fibroblasts senscence in vitro: pattern of cell division and life span as a function of cell density.

The pattern of cell division, ageing and death of cultured chick embryo fibroblasts inoculated at a wide range of cell densities is described. Cell populations seeded at densities of 2.1 x 10-3 to 3.1 x 10-4 cells per cm-2 double between 39 and 17 times respectively while their life span at all densities remains 57 puls or minus 3 days. Thus, under the experimental conditions employed, the life span of cultured embryonic chick cells is a function of calendar rather than mitotic time. We also find that the duration of phase III and the generation time of the cells during this period are proportional to the density of the culture. Moreover, the division rate of cells inoculated at low densities (4.2-31.0 x 10-2 cells per cm-2) remains constant throughout their entire lifetime. It is suggested that the decline in the proliferative capacity of chick cells ageing in vitro is a function of both their density and their age.


Correlates of satisfaction and dissatisfaction with medical care: a community perspective.

The attitude of the public toward physicians and medical services is an issue of current concern and debate.  To address this problem, an instrument was developed using Thurstone scaling methods in conjunction with a Likert format and a modified scoring technique.  Following pretesting of the instrument among both patient and population samples, a survey was conducted among the residents of a probability sample of households in a city of 200,000 people.  The attitude questionnaire was completed by 1,713 adults in 1,112 households.  Overall, attitudes were favorable toward the professional competency and the personal qualities of physicians.  Accessibility, including costs and convenience, were less highly regarded.  Men were less satisfied than women and blacks less satisfied than whites.  Particularly negative attitudes were expressed toward the personal qualities of physicians by young blacks, whereas among blacks over 60 the negative effect was toward cost and convenience.  Having a regular physician and long attendance with that physician were correlated with positive attitudes.  The most negative sentiment was expressed by women without regular source of care.  Medical services are being sought and obtained by a large segment of society, but problems of costs and acceptability for the elderly, low social class persons, members of large families, and for blacks still remain.


A study of consumer attitudes about health care: the control, cost, and financing of health services.

The delivery of health care had emerged as one of the most important political issues of the 1970's, yet public attitudes about health issues remains a relatively unexplored subject.  Little is known about the public's opinion of who should control the delivery of health care, about how the costs of health care are perceived, or about how the delivery of care should be financed.  This paper relates respondent attitudes on these subjects to attitudes about criteria that determine the respondent's choice of ambulatory care facility and to socioeconomic, political, and other demographic characteristics.  The data are derived from a survey (N=521) of households representative of the area of Rochester, New York.


Concomitant tissue accumulation of "collangen-associated" sialoglycoproteins and salt-insoluble collagen during rat skin maturation. a brief note.

In the course of rat skin maturation, the quantity of sialoglycoproteins solubilized by collagenase-digestion increased parallel to the accumulation of insoluble collagen. This suggested the existence of sialoglycoproteins which are associated with collagen, perhaps, during the development of the extracellular matrix.


Dimensions of patient attitudes regarding doctors and medical care services.

The factor analytic development and validation of numerous index scores to measure patient attitudes regarding characteristics of doctors and medical care services is described. Index scores meeting factor analytic criteria and found to be reliable were used to study the nature and number of attitudinal dimensions underlying patient satisfaction. The use of index scores which have met logical and empirical criteria is in contrast to the common practice of using individual questionnaire items as the unit of analysis. Four major dimensions of patient attitudes were identified and described, including attitudes toward doctor conduct (humanness and quality) and such enabling components as availability of services, continuity/convenience of care and access mechanisms (cost, payment mechanisms, and ease of emergency care). Measures of attitudes toward caring (humanness) and curing (quality/competence) aspects of doctor conduct appear to reflect the same underlying attitudinal dimension. Findings are discussed in relation to concepts and measures mentioned in the published literature and suggestions are offered for future research.


Consumer evaluation of health services: implications for methodology and health care policy.

Consumer evaluation research is defined and analyzed as an experimental model for establishing a link between social science research and public policy. The paper reports the results of an 18-month longitudinal study of an experimental citizen evaluation group. Participant observation was the method used to organize the data. The impact of the model on methodological issues, such as objectivity, researcher autonomy, and control over research decision-making are discussed. Implications of the consumer evaluation model for integrating social research and health policy formulation are analyzed and principles of citizen evaluation research are presented.


Task analysis in health manpower development and utilization.

Job analysis and tast analysis are systems methods which examine the functions of individuals and allocate these functions into job descriptions which can make for a better utilization of health manpower by a restructuring of the jobs of health professionals and a restructuring of curricula as a reflection of the jobs to be performed. These analytic methods have had limited application to the health field. This methodology was applied to the education of a nonphysician family health team for an inner-city prepaid comprehensive health center and staff development at a health maintenance organization, and has served as the basis for the curriculum of an associate degree physician's assistant program and a baccalaureate degree health associate program. Among the advantages for the application of this method are the interrelationship of resulting jobs rather than isolation and career mobility in both the work situation and curricula. Constraints include the lack of entry level jobs, the prestige of the Bachelor's Degree, the need for proficiency tests for advanced standing, tuition costs, and the traditional attitudes of health agencies on release time and educational institutions on basic requirements.


Epidemiology of laryngeal cancer.

The patients with cancer of the larynx at the Ear, Nose and Throat Department in Zagreb during the period from 1945 to 1972, and the cases of laryngeal cancer at the Institute of Public Health of Croatia, were examined epidemiologically. The patients were from all parts of Croatia (West and south part of Yugoslavia) with the characteristics of Mediterranean and Continental climate. The following factors were discussed: age and sex distribution, localization of the tumor in three compartments of larynx, relationship between the villages and cities, occupation (peasants, workers and intellectual people), histologic types and the etiological factors (smoking and alcohol.


An epidemiological study of laryngeal cancer in Japan.

This report presents the findings of an epidemiological study of laryngeal cancer in Japan, based on 6,360 cases treated and registered during the 10-year period from 1960 through 1969. The number of the patients increased 1.5 times from 1960 to 1969. Geographically the absolute number of recorded cases was proportional to the population density; in other words, it was larger in heavily urbanized areas and smaller in rural regions. An anatomical classification revealed that the incidence of supraglottic and glottic cancer was about equal (3,121 and 3,176 cases), and subglottic cancer was only 1 percent of the total. Histologically, 98.6 percent were of the squamous cell carcinoma and 1.4 percent were of the basal cell carcinoma, adenocarcinoma, transitional cell carcinoma, etc. As to the age and sex distribution, the majority of the patients were 50 to 70 years old, and those in their 60's were most numerous. The ratio between men and women was 9.6 to 1. 56.1 percent of the patients surveyed were found to have a blood relation with a history of cancer and 31 percent were engaged in occupations where they used their voices frequently. Smoking habits were found in 96 percent of the patients surveyed and as many as 52 percent came under category of heavy smokers. Cigarette smoking might be regarded as a significant factor in laryngeal cancer, while alcohol consumption was not as significant a causal factor as smoking. The living environment had no explicit relationship to laryngeal cancer in the above-mentioned period of years.


Medial orbital blow-out fracture: a case report.

A case report of orbital blow-out fracture with medial rectus muscle entrapment is described. Over one-third of the patients with blow-out fractures of the orbital floor also sustain medial wall injury. Five previous case reports of medial entrapment are reviewed. The mechanism of injury is hydraulic, and the medial muscle incarceration in the fracture may produce an orbital retraction syndrome. Exploratory surgery is recommended through an external orbito-ethmoid approach.


The sequential septo-rhinoplasty.

In septo-rhinoplastic surgery it is helpful to follow a logical series of stages for correcting abnormalities of various anatomic components of the nose. A suggested order of staging of the typical nasal plastic operation is presented. By following a logical sequence of surgical stages, the least correctable components are modified first, and each successive stage of the procedure is related to the result obtained in the previous stage. Technical considerations are presented in each stage suggested, and the analysis and correction of intranasal abnormalities to restore normal nasal function is emphasized. Specific preoperative problems and the results of suggested methods of correction are presented.


[Electrocardiographic features and vectorial analysis of cardiac potentials in electric shock-induced ventricular fibrillation (author's transl)].

The authors examined the electrocardiographic features of ventricular fibrillation and other ventricular paroxysms induced by electric shock in the guinea pig. The analysis of the electrocardiographic patterns, as well as the vectorial study of the cardiac potentials during repeated episodes of ventricular "anarchy" induced in more than forty animals, showed the following data: 1. following electric shock, ventricular paroxysms appear, featuring paroxysmal tachycardia, typical or impure flutter, tachycardia--either "torsade de pointe" or "spindle" type, and typical ventricular fibrillation. Such different electrocardiographic patterns represent evolutive stages of electric activity disorganization, leading to a complete ventricular "anarchy". Such steps may reverse when reorganization of the electric activity and spontaneous defibrillation occur; 2. an attempt can be made at present to classify ventricualr paroxysms, thus eleminating semeiotic and semantic errors, still present in the literature, and providing a standardization of both nomenclature and electrocardiographic interpretation; 3. during fibrillation, the mean ventricular rate decays, featuring an exponential curve. This phenomenon accounts for a metabolic depletion of the myocardium: the higher the number of fibrillation episodes previously induced and subsided (either spontaneously or not) in the same animal, the faster the course of the phenomenon; 4. the vectorial analysis of the fibrillation potentials and, particularly, the graphic construction of "depolarization" and "repolarization" vectorcardiograms, in the differenttypes or variants of ventricular paroxysms, show that the basic mechanisms leading to ventricular electric activity disgregation are the multiple re-entry and the irregular spreading of the activation front; 5. on the basis of the acquired data, the authors believe that the "circus movement" theory (Wiggers) is still the most suitable for explaining the onset and the evolution of ventricualr fibrillation.


[A survey of work environment of upper-shoe factories. (author's transl)].

A research was carried out by the authors in order to asses the environmental, hygienic, microclimatic and risky features of the work environment of some upper-shoe factories, mainly in relation to the onset of polyneuropathy. The close connection between work environment and some noxious chemical compounds is underlined, and the opportunity to set up an organic regulation of the matter, stressed.


[Maximal mid-exiratory flow (MMEF) in the evolution of the respiratory functional patter of silicosis. (author's transl)].

A follow up study of VC, FEV and MMEF was performed by the authors in forty silicotic patients, mainly in order to find out if MMEF were more sensitive than VC and FEV 1 IN detecting respiratory function impairment in the follow up of silicosis. In patients with moderate bronchial obstruction, a statistically significant difference was found between themean values of MMEF measured in two different instances: such a finding suggests a greater MMEF reduction in the early stages of silicosis. In 22 subjects with moderate respiratory function impairment (VC and FEV1 less than or equal 40% predicted values), MMEF was found to be, percentually, more decreased than FEV1: the difference was statistically significant. It is therefore concluded that MMEF changes in the follow up examination of silicosis are more sensitive than other functional indexes.


Basic components in the motor performance of children six to nine years of age.

Six factor solutions (three orthogonal and three oblique) were used to extract factors from the intercorrelation matrices of 47 motor performance and physical growth measures obtained on 71 boys and 74 girls, ages six to 9.9 years. Twelve factors with eigen values in excess of 1.00 were extracted from both the boys' and girls' data. The six factors that accounted for a major proportion of the variance in both sexes were tentatively identified as (1) Strength-Power-Body size, (2) Gross Limb-Eye Coordination, (3) Fine Visual Motor Coordination, (4) Fat or Dead Weight, (5) Balance, and (6) Leg Power and Coordination. Similarity in the factor structures of the sexes was evident from the application of a procedure for the quantification of the relationships between factors extracted from data in different groups of subjects. With this sample of children substantial relationships were obtained between eight of the ten factors which were common to both sexes.


Computer generated track and field scoring tables: II. Theoretical foundation and development of a model.

An investigation is made into the subject of scoring tables for track and field with emphasis on the application of computers to calculate and output the tables. The resulting scoring tables represent an attempt to describe the effective quality of performance for track and field events. This paper is published in three parts. The first portion reviewed the historical development of scoring tables. This part concerns the theoretical foundation and development of a mathematical model. A set of underlying principles and construction guidelines are established as a basis for all scoring tables. In order to satisfy the goals, a model which includes an exponential term is developed. The concept of a zero offset is introduced as a boundary value for the low-level performances. The final part concerns an evaluation of the model and an analysis of the point scores for different events.


The role of blood flow in limiting maximal metabolic rate in muscle.

To determine the role of blood flow in limiting maximal metabolic rate, the contralateral femoral artery was cannulated and the blood passed through a pump (controlled flow perfusion) or a bypass (self perfusion) to the artery feeding the canine gastrocnemius-plantaris muscle group (N = 15). After a period of self perfusion, the pumped flow was set at the spontaneous level. The muscle was stimulated at 4 or 5 twitches per second to produce a maximal metabolic rate and the pumped flow increased until the precontraction perfusion pressure was reached. After 5 minutes, the flow was increased (perfusion pressure around 200 mm Hg) and then the flow was returned to initial levels and subsequently decreased below this. Oxygen uptake (Vo2) was determined in the fifth minute at each flow level. Isometric tension was measured with a myograph. When the flow was increased above that during the initial contraction period, tension and Vo2 increased above their initial levels. When returned to initial levels, tension and Vo2 followed. Flows below this level resulted in Vo2 and tension decreasing below initial levels. Autoregulation transients were present before and after contraction. It appears that maximal metabolic rate and contractile performance of in situ dog muscles with autoregulating vascular beds are normally limited by blood flow.


Postexercise glycogen replenishment in untrained animals: denervation, tenotomy effects.

To test the hypothesis that an intact nerve supply is essential to normal replenishment of muscle glycogen after exhaustive exercise, glycogen concentration in normal gastrocnemius muscles from guinea pigs exhausted 48 hr previously was compared to glycogen in contralateral muscles that had been denervated at the muscle or high in the thigh immediately after exercise. Each animal of another group underwent tenotomy of one Achilles tendon after exercise so that any effect of disuse could be distinguished from effects of denervation. All muscles were able to replenish glycogen to normal control values 48 hr after exercise and surgery; there were no significant (greater than .05) effects of any of the surgical interventions. Therefore, it appears that glycogen concentration in skeletal muscle 48 hr after exhaustive exercise is independent of both neural phenomena and muscle tension.


Cleat-surface friction on new and old AstroTurf.

The authors have studied the alterations in cleat-surface friction of AstroTurf associated with use and exposure. Three cleat types were studied on five year old turf and on an unused, unexposed turf sample of the same production batch. Tests were carried out with and against surface grain under wet and dry conditions. It was found that with use and exposure the surface friction of AstroTurf does change, affecting both player performance and safety.


Comparison of effects of training on Vo2max in girls and young women.

Eight girls (12-13 years) and eight young women (18-21 years) trained for 14 weeks. The training sessions were conducted for 30 minutes, 3 times weekly and consisted of running and bench stepping. A treadmill test was used to elicit Vo2max, VEmax, and HR max and it was administered prior to training and after the 2nd, 6th, and 14th weeks of the training. The same test was administered twice, initially and after 14 weeks, to the eight girls and eight women in control groups. After training, both the girls and women had a significantly higher Vo2max regardless of whether Vo2max was expressed in l/min or ml/kg per min. The training groups also increased their VEmax values significantly, however, HR max was not influenced by the training. Not only did the girls and women increase in their Vo2max by a similar magnitude, but they also demonstrated similar rates of change in Vo2max during the training. In addition the most rapid rates of improvement occurred during the initial two weeks of training, and both training groups improved throughout the 14 weeks.


Effects of mode of training on cardiovascular function and body composition of adult men.

The purpose of this investigation was to determine the comparative effects on middle-aged men of training by running, walking, and bicycling. Sedentary men (X age = 38 yrs), who volunteered to participate, were assigned randomly to one of the following training groups: I, running (n = 9); II, walking (n = 9); and III, bicycling (n = 8). All groups trained for 30 min, 3 times/week for 20 weeks at 85 to 90% of maximal heart rate. A control group of seven men of similar qualifications also were evaluated. Training heart rates averaged 90%, 87%, and 87% of maximum for groups I, II, and III, respectively. All experimental groups improved significantly in cardiovascular and body composition measures. The former was shown by significant increases in Vo2max, VEmax, and O2 pulse and a significant decrease in resting heart rate. Body composition results showed that the experimental groups had a significant reduction in body weight, skinfold fat, and abdominal girth measurements. The control group showed no significant changes for any of the variables. It was concluded that improvement in the experimental groups was independent of mode of training.


Effect of warm-up on metabolic responses to strenuous exercise.

Aerobic and anaerobic energy transformations were measured in two trained runners during 90-sec treadmill runs at 23.6 km/hr (2% grade). The runs were preceded by rest or either of two warm-ups: 1) 15-min run at 10 km/hr, or 2) 15-min run at 10 km/hr followed by 3-min standing. Compared with runs without warm-up, during the third half minute of runs following both types of warm-up 11% greater heart rates (HR), 8% greater oxygen consumption (Vo2), and unchanged ventilation were recorded. The rate constant of the approach of Vo2 to O2 in the first minute of work was unaffected by warm-up. Runs following either warm-up resulted in 25% lower lactate production; during these runs 3 to 4 degrees C higher gastrocnemius muscle temperatures (Tm) were maintained. The differences in HR, Vo2, and Tm continued throughout exhausting 5-min runs at 20.9 km/hr (2% grade). An elevated muscle temperature may therefore be requisite for the maximal aerobic response to a short exhausting run.