Role of thyroid gland in oxygen toxicity. The effects of hyperoxia at ambient pressure on thyroid function and thyroid hormone metabolism have been assessed. Thyroidal activity was depressed in mice and rats by exposure to hyperoxia, due at least in part to a decrease in the rate of secretion of pituitary thyrotropin. The effects of hyperoxia on the peripheral deiodination of thyroxine (T4) were dependent on the concentration of oxygen employed and/or the duration of exposure; exposure to 40--80% oxygen for 96 h resulted in decreases in the rate of deiodination and in the deiodinative clearance of [125I]T4. Hyperoxia also resulted in a marked fall in the serum concentration of endogenous T4 and a decrease in T4-binding activity in serum. Many of these effects of hyperoxia were prevented by the concomitanat administration of large amounts of vitamin E (alpha-tocopherol acetate). These decreases in thyroid function and T4 metabolism were associated with a decrease in the rate of whole body oxygen consumption. Thus, the deleterious effects of oxygen in the rat were not due, even in part, to an oxygen-induced hyperthyroid state in the peripheral tissues.


Synaptosomal [125I]triiodothyronine after intravenous [125I]thyroxine. We administered [125I]thyroxine intravenously to adult male rats and measured uptake and subcellular distribution of the hormone and its metabolites in brain. Fractional brain uptake decreased after a large dose of iodothyronine, providing evidence for saturability of the uptake mechanism. Well-defined patterns of regional and subcellular labeling were noted within 1 h after [125I]thyroxine injection. Radioactivity in synaptosomes was always greater than in any other particle separated per gram of brain, increasing linearly relative to radioactivity in brain cytosol during the 1st h. Although [125I]triiodothyronine derived from [125I]thyroxine was not identified in serum at any time interval, it was measurable in synaptosomes within 20 min and in brain cytosol within 1 h after labeled hormone administration. Concentrations of the radioactive metabolite were twofold greater and ratios of [125I]triiodothyronine to [125I]thyroxine concentration were threefold greater in synaptosomes than in cytosol. Therefore, thyroxine may be converted to triiodothyronine within nerve terminals. Synaptosomal localization of iodothyronines and their metabolites may be relevant to the marked central and peripheral adrenergic nervous system effects of these aromatic amino acid hormones.


Hepatic transport kinetics and plasma disappearance curves: distributed modeling versus conventional approach. The conventional approach to estimating hepatic transfer coefficients from the plasma disappearance curve ignores the effects of blood flow in the splanchnic and peripheral circulations. The effect of these simplifying assumptions on derived estimates of the rate constants has never been studied. To examine this problem we have constructed a distributed model that takes account of intrahepatic concentration profiles, nonuniform blood-flow distribution in the sinusoids, and delayed mixing in the peripheral circulation. Solutions to the new model constructed by numerical inversion of the Laplace transform afford a comparison between the new model and the conventional one. The sensitivity of the conventional equations to experimental error has also been evaluated. The results indicate that conventional estimates of the rate constants for hepatic uptake and cell-to-plasma efflux are subject to a systematic underestimate, the errors increasing rapidly with the initial extraction fraction. Estimates of the uptake constant obtained from the initial slope are especially susceptible to circulatory distortions and proved unacceptable even at low values of the initial extraction fraction. The liver content at 3 min did not in general provide a reliable index to these errors. In contrast to these problems, the conventional model returns generally accurate estimates of the steady-state plasma clearance and the rate constant for excretion.


Disruptive effect of test meals on interdigestive motor complex in dogs. The disruptive effect of food and food components on the migrating myoelectric complex (MMC) was studied in conscious dogs. Three types of test meals were fed, and the interval between feeding and the reappearance of the first phase III of the MMC was determined. When commercial dog food was used a linear relation was observed btween the quantity of food (expressed as kcal/kg body wt) and the duration of the disruption of the MMC. Equicaloric amounts of the three major food components disrupted the MMC pattern for periods of time that were related to the nature of the food: the effect of arachis oil lasted longer than that of sucrose and much longer than that of milk protein. Medium chain triglycerides had a potent disruptive effect. Mixtures of these food components produced a disruptive effect that could not be calculated from the individual effect of each component. Phase III of the first and second MMC after feeding started at a lower level of the intestine than after a long fast. The duration of disruption of the MMC after a meal depends much more on the physicochemical composition of the food than on its volume or amount of calories.


Role of gastrin and insulin in postprandial disruption of migrating complex in dogs. The duration of the disruption of the interdigestive migrating myoelectric complex (MMC) by various test meals in dogs was correlated with changes in serum gastrin and insulin levels. The test meals consisted of milk protein, sucrose, arachis oil and medium chain triglycerides (MCT). Intravenous infusions of glucose 20% were also used. Electrical activity of the small intestine was registered by means of electrodes implanted over the entire length of the gut. Hormones were assayed by radioimmunoassay techniques. The insulin level rose significantly after both the glucose infusion and the sucrose meal. The rise was small after the milk protein meal and nothing after arachis oil and MCT. Gastrin level was not changed by arachis oil or MCT and rose slightly after sucrose and milk protein. The MMC was not disrupted by glucose infusions, but was disrupted for 5--7 h by archis oil and for 6--12 h by MCT. We conclude that in dogs neither gastrin nor insulin have an important role in the mechanism of disruption of the MMC after feeding.


A basic relationship between gastric and duodenal motilities in chickens. Chickens were chronically fitted with a duodenal cannula and pairs of electrodes implanted in the wall of the muscular stomach, duodenum and ileum. Smooth muscle electrical activity was recorded in both fed and fasted conditions under a 12--12 h dark-light schedule. Two major patterns of activity were identified. The first consisted of spike bursts that propagated rapidly either aborally from the stomach or orally from the ileum. Aborad-propagated spike bursts were most frequent during the daytime; this circadian variation was abolished by vagotomy, which also increased the frequency of orad-propagated spike bursts. The second pattern was characterized by periods of repetitive spike bursts lasting 3--10 min and spreading aborally at a slower rate. In the fasted chicken, the daily frequency was increased and the period of repetitive spike bursts resembled the prolonged bursts of spike potentials recorded in the feline small intestine. The results suggest that the propulsion of digesta might depend on the ratio of spike bursts moving aborally from the stomach to those moving orally from the ileum. Both factors were influenced by the level of stomach activity.


Folic acid transport by mammalian small intestine. The unidirectional influx of folic acid across the mucosal border of hamster duodenum and rat jejunum was determined. Influx follows saturation kinetics, is sodium-dependent, and is inhibited by methotrexate and is sodium-dependent, and is inhbited by methotrexate and folinic acid in the mucosal bathing solution. In hamster duodenum, the maximal influx is 1.2 nmol/(cm2.h), and the folic acid concentration required to give a half maximal influx (Km) is 7.2 micron.. At mucosal folic acid concentration of 1.5 micron, influx is reduced at least 65% by removal of sodium from the bathing solution. The influx process is significantly inhibited by cyanide and 2,4-dinitrophenol. The possibility was evaluated that the acidic microclimate at the brush border regulates the rate of folic acid transport and that inhibition of transmural transport by sodium-free media, ouabain, and methotrexate is brought about indirectly by an increase in pH of the microclimate. The data favor the alternative concept of a sodium-dependent carrier mechanism for entry of folic acid into the cells. The information presented is consistent with active transport of folic acid by a sodium-gradient mechanism, but additional information will be necessary to substantiate such a model.


Regional differences in potassium content of smooth muscle from opossum esophagus. Strips from the proximal part of the smooth muscle segment of opossum esophagus have a significantly higher potassium content (50 +/- 3 meq/kg) than those from the distal part (38 +/- 3 meq/kg). There are no significant differences between the two regions in content of sodium (65 +/- 4 meq/kg in proximal, 71 +/- 3 meq/kg in distal) or chloride (48 +/- 10 meq/kg in proximal, 42 +/- 5 meq/ kg in distal). The mean [14C]inulin uptake is 240 +/- 10 ml/kg in both proximal and distal strips. [14C]polyethylene glycol uptake is smaller and [14C]sucrose and [14C]mannitol uptake in both areas are larger than that of inulin. Intracellular potassium concentration (based on the inulin uptake as an estimate of the extracellular space volume) is significantly higher proximally (71 +/- 3 mM) than distally (52 +/- mM). Ouabain, 10(-4) M, increases the intracellular concentration of sodium and decreases the intracellular concentration of potassium in both the proximal and distal segment. The efflux of 86Rb, measured by a washout technique, is higher in the distal than in the proximal smooth muscle segment. A difference in membrane permeability to rubidium and hence, potassium between proximal and distal smooth muscle segments may account in part for the different intracellular potassium concentrations.


Interaction of caerulein and secretin on pancreatic size and composition in rat. Rats were given injections of caerulein, secretin, or a combination of these two peptides subcutaneously 3 times daily for 5, 10, or 15 days. Caerulein produced significant dose- and time-dependent increases in pancreatic weight and content of DNA, RNA, protein, amylase, and trypsinogen. Secretin produced significant increases in pancreatic weight and content of RNA and lipase after 15 days of treatment. After only 5 days of treatment with a combination of secretin plus caerulein, pancreatic weight and content of RNA and protein more than doubled, and trypsinogen content increased more than fivefold. Comparing the averages across the 5-, 10-, and 15-day values, increases in weight, protein, and trypsinogen with the combination of secretin plus caerulein were significantly greater than the sum of the effects of the peptides given singly. Using increase in DNA content as an index of hyperplasia and increases in the ratios of pancreatic weight, RNA content, and protein content to DNA content as indices of hypertrophy, we concluded that caerulein produced both hyperplasia and hypertrophy of rat pancreatic acinar cells. Secretin markedly augmented the hypertrophic action of caerulein but did not alter its hyperplastic action.


Cellular and paracellular calcium transport in rat ileum: effects of dietary calcium. The mechanism of calcium transport and its modulation by dietary Ca restriction in rat ileum have been investigated employing an in vitro voltage-clamp technique. Ca fluxes directed from mucosa-to-serosa (J(Ca)ms) and serosa-to-mucosa (J(Ca)sm) exhibit components consistent with both cellular and paracellular pathways. The cellular Ca fluxes are both dependent on medium Na and are abolished at 10 degrees C. In addition, a cellular component of J(Ca)ms displays voltage dependence. A low-calcium diet, which induces the formation of 1,25-dihydroxycholecalciferol, causes a marked increase in both cellular J(Ca)ms and Ca influx from media to cells with little absolute effect on the paracellular pathway. This evidence is consistent with the existence of electrogenic Na-Ca exchange pumps at both brush-border and basolateral membranes, driven in part by the Na electrochemical gradient. Dietary Ca conditioning may control the direction of net Ca transport by modulation of the saturable influx process at the brush border.


Kinetics of amylase release by dispersed acini prepared from guinea pig pancreas. When incubated with a secretagogue such as cholecystokinin (CCK), dispersed acini prepared from guinea pig pancreas released substantially more amylase than did dispersed single acinar cells. With CCK the rate of amylase release from dispersed acini decreased after 5 min of incubation and remained constant for the subsequent 25 min. The magnitude of the reduction in the rate of amylase release after 5 min was greater with higher concentrations of CCK. With vasoactive intestinal peptide (VIP), the rate of amylase release remained constant for at least 30 min. With CCK plus VIP, potentiation of the rate of amylase release occurred only during the first 15 min of incubation. After 15 min of incubation, the effects of the two peptides were additive. When dispersed acini were first incubated with CCK, potentiation of amylase release occurred only when VIP was added during the initial 10 min of incubation. In contrast, when cells were first incubated with VIP, potentiation of amylase release occurred when CCK was added as long as 30 min after VIP.


Interactions between volume expansion or diuretics and compensatory adaptation. Glomerular filtration rate, urine flow, and Na excretion were measured 3--4 h after unilateral nephrectomy (1/2Nex) or sham operation in unanesthetized rats infused with isotonic saline (0.05--0.75 ml/min) and additionally injected with acetazolamind (20 mg/kg i.p.) or furosemide (5 mg/kg i.p., or 0.2 mg/kg i.v., or 2.0 mg/kg i.v.) or with both agents. Glomerular filtration rate of unilaterally nephrectomized rats averaged 50% of controls. Under all experimental conditions investigated, absolute water and Na excretions were similar in 1/2Nex and sham-operated rats. The fractional excretion (FE) of water and Na was increased 1.5- to 2.2-fold in 1/2Nex animals. The diuretic effects of volume expansion, of the two diuretic agents, and of contralateral nephrectomy consistently were additive. The "compensatory" increase of FESa following contralateral nephrectomy entailed a proportional increase of the diuretic effects of agents given subsequently. Urinary furosemide excretion 15 min after intravenous injection in unilaterally nephrectomized rats was smaller than in controls. The additivity of the diuretic effects of contralateral nephrectomy ("compensatory adaptation") and volume expansion and/or diuretic agents appears to be partly explained by different sites of action.


Bidirectional sodium fluxes across the placenta of conscious sheep. Conscious pregnant sheep in the last 3 wk of gestation were studied 1--3 days after surgery. Fetal plasma sodium concentration was significantly lower than maternal. A mean electrical potential difference (PD) of 34 +/- 4 (SE) mV (n = 24) was recorded between maternal and fetal intravascular catheters, the mother being positive with reference to fetus. Unidirectional fetomaternal (Jf leads to m) and maternofetal (Jm leads to f) sodium fluxes were determined by application of Fick's principle to uterine and umbilical circulations following injection of 22NaCl or 24NaCl to fetus or mother, respectively. Blood flows were measured by an antipyrine technique. Jm leads to f = 0.142 +/- 0.029 mmol/min (n = 10); Jf leads to m =0.137 +/- 0.015 mmol/min (n = 21). Jm leads to f increased as a linear function of calculated fetal weight. In seven sheep both Jm leads to f and Jf leads to m were measured in a single experiment. The measured ratio Jm leads to f/Jf leads to m was significantly different from the ratio predicted using Ussing's flux ratio equation. There is probably a transplacental sodium pump active in the direction fetus to mother.


Actions of adrenergic agonists on isolated excretory ducts of submandibular glands. The effects of norepinephrine and isoproterenol on the transepithelial potential difference (PD) and the net transepithelial fluxes of Na, K, Cl, and HCO3 of the main ducts of the submandibular glands of rats and rabbits have been studied by microperfusion of ducts incubated in vitro in an artifical bathing medium. In the rabbit duct, both catecholamines caused depolarization and reduced transepithelial Na reabsorption at concentrations above 10(-29) M. In the rat duct, norepinephrine reduced PD and net Na reabsorption and, in addition, inhibited net K secretion at concentrations of 10(-7) M and above. Isoproterenol also depolarized the duct and reduced net K reabsorption, but at concentrations of 10(-9) M it stimulated net Na reabsorption, whereas at concentrations of 10(-4) M it inhibited Na reabsorption. The stimulation caused by isoproterenol at low concentrations could be blocked by prior administration of propranolol. The results suggest that electrolyte transport, by both rat and rabbit ducts, may be influenced not only by sympathetic nerve activity but also by physiological changes in the concentrations of circulating catecholamines. Inconsistencies in the literature regarding the sensitivity of the rabbit duct to catecholamines and the response of the rat duct to isoproterenol have now been resolved.


Effect of decreased renal sympathetic nerve activity on renal tubular sodium reabsorption. The effect of decreases in renal sympathetic nerve activity on renal tubular sodium reabsorption was examined in anesthetized dogs. Reflex decreases in renal sympathetic nerve activity were produced by left atrial distention and stellate ganglion stimulation. Both interventions produced significant decreases in directly recorded efferent renal sympathetic nerve activity of 42 and 36%, respectively. With renal perfusion pressure held constant, neither glomerular filtration rate nor renal blood flow were significantly altered, but significant and reversible increases in urine flow and sodium excretion occurred. These studies demonstrate that reflex decreases in efferent renal sympathetic nerve activity result in decreases in renal tubular sodium reabsorption without changes in renal hemodynamics.


Renal histamine H1 and H2 receptors: characterization and functional significance. Canine experiments were designed to determine if both histamine H1 and H2 receptors are present in the renal circulation. Renal blood flow (RBF) increased steeply over the first minute of intra-arterial histamine infusion, then increased gradually to a plateau in 3--5 min. Infusion of either histamine + H2 antagonist or of H1 agonist produced the initial rapid increase in RBF, whereas infusion of either histamine + H1 antagonist or of H2 antagonist produced a slower but more sustained increase in RBF. Histamine significantly increased urine flow rate (V), chloride excretion, and glomerular filtration rate (GFR). Infusion of the H2 agonist also increased V and Cl excretion without affecting GFR. By contrast H1 agonist significantly reduced V and Cl excretion and tended to reduce GFR (P less than 0.1 greater than 0.05). Histamine, H1 agonist, and H2 agonist each increased inner cortical more than outer cortical blood flow. These data suggest that 1) H1 and H2 receptors are present in the renal vasculature, 2) changes in intrarenal blood flow distribution are not responsible for histamine-induced diuresis, and 3) H1 receptors are primarily postglomerular while H2 receptors exhibit both pre- and postglomerular distribution.


Relative sodium-to-chloride permeability in the proximal convoluted tubule. Electrophysiological techniques were used in isolated perfused proximal convoluted tubules (PCT) to examine the effect of changes in bath protein concentration on paracellular properties and of active salt transport on relative sodium-to-chloride permeability (PNa/PCl). Control transepithelial potential difference (PD) and NaCl dilution potentials were determined in tubules perfused and bathed with an ultrafiltrate-like solution. PNa/PCl was calculated from the NaCl dilution potential. In the first series of experiments PD and PNa/PCl were redetermined in the same PCT following three experimental maneuvers known to inhibit active salt transport. Addition of 10(-5) M ouabain to the bath, removal of luminal glucose and alanine, and removal of luminal glucose, alanine, bicarbonate, and acetate reduced PD but did not alter the NaCl dilution potential, and therefore PNa/PCl was constant. Constant PNa/PCl in these experiments suggests a) that lowering bath NaCl concentration does not change transcellular current flow, b) that PNa/PCl reflects the ion selectivity of the paracellular pathway, and c) that the ion selectivity of the paracellular pathway is independent of active salt transport. In the second set of experiments PD and PNA/PCl were redetermined following addition of protein to the bath. Neither PD nor PNa/PCl was altered. Analyses of these data argue against modulation of paracellular permeability by bath protein in the in vitro rabbit PCT and suggest that the ion selectivity of the paracellular pathway is determined predominantly by junctional complexes rather than lateral intercellular spaces.


Effect of exogenous and endogenous angiotensin II in the isolated perfused rat kidney. Rat kidneys were perfused with an artificial solution at constant pressure. The infusion of angiotensin II (AII) (1.5--6 ng min-1) reduced renal perfusate flow (RPF) from 36.6 +/- 2.4 to 19.3 +/- 1.4 ml min-1 (P less than 0.001) (n = 13); GFR rose from 0.48 +/- 0.06 to 0.63 +/- 0.04 ml min-1 (P less than 0.05), and filtration fraction (FF) rose accordingly from 0.015 +/- 0.002 to 0.033 +/- 0.003 (P greater than 0.01). The same results were obtained with purified renin substrate (synthetic tetradecapeptide, 100 ng min-1, n = 8); RPF fell from 31.5 +/- 2.9 to 17.2 +/- 2 ml min-1 (P less than 0.001), GFR rose from 0.36 +/- 0.05 to 0.51 +/- 0.04 ml min-1 (P less than 0.05), and FF increased from 0.021 +/- 0.002 to 0.034 +/- 0.006 (P less than 0.01). The effects of renin substrate were completely prevented by the converting enzyme inhibitor SQ 20,881 (3 X 10(-5) M). In another six experiments the effects of renin substrate at the same dose were fully reversed by addition of the analogue [Sar1,Ala8]AII. We interpret these findings to indicate that both exogenous and endogenous AII produce preferential vasoconstriction of the efferent arteriole, increasing the driving force for ultrafiltration and thereby maintaining or increasing GFR in the face of a reduced plasma flow.


Transcellular and paracellular tracer chloride fluxes in Necturus proximal tubule. Necturus proximal tubule lumen was filled with solutions of Na36Cl or [36Cl]tetramethylammonium ([36Cl]TMA) and the tracer disappearance was measured. With these tracers it was possible to differentiate between chloride fluxes across the cellular and the extracellular shunt pathways. Since it was previously shown that chloride does not enter tubule cells from the lumen unless Na is also present in the lumen, the [36Cl]TMA disappearance rate gave the shunt flux of chloride while the Na36Cl disappearance rate gave the sum of the transcellular and the shunt fluxes. The transcellular tracer chloride flux was unaffected by changes in the transepithelial potential difference, and the rate constant for the chloride flux from lumen to cell was identical to that previously reported for luminal sodium entry. These observations support the conclusion that a coupled transport of NaCl, in an electrically silent form, occurs across the luminal membrane of the Necturus proximal tubule cell. Shunt chloride flux was directly proportional to the electrical driving force, indicating diffusional chloride movement out of the lumen into the shunt pathway.


A model for transepithelial fluid transport. A number of experimental observations which are not easily, or at all, accommodated within the framework of the natriocentric theory for transepithelial fluid transport are discussed. These are shown to be not merely accommodated but actually predicted by a simple model for fluid transport in which the major osmotic force leading to fluid transport derives from solutes other than NaCl. The model is then analyzed for feasibility in light of existing data relating to reflection coefficients for NaCl and hydraulic conductivity. Certain lines of evidence for specific active sodium transport are critically reexamined.


A network thermodynamic model of salt and water flow across the kidney proximal tubule. This network thermodynamic model of kidney proximal tubule epithelium treats coupled salt and water flow across each component membrane of the epithelium. We investigate the effects of various relative internal parameter values on the concentration of transepithelial flow, the concentrations in the cell and interspace, and the distribution of flows between cellular and paracellular routes. Best fit is obtaine if the apical and basolateral membrane reflection coefficients (or) are equal. The measured transepithelial filtration coefficient, Lp, is a function not only of the component Lps but also of the internal concentrations, or's, and permeabilities. For the given system topology (i.e., connectedness), parameters of component membranes must be within a narrow range to be consistent with experimental results. The dependence of the concentration of transported fluid on the balance between the solute pump rate and the transepithelial volume flow driving force is shown. This has implications for the effects of peritubular or lumen oncotic pressure on salt and water flow. With Appendix B of this paper and a user's guide for a circuit-simulation package (e.g., SPICE or PCAP) the reader can perform similar network analyses of transport models himself.


Myocardial perfusion and function during acute right ventricular systolic hypertension. Hemodynamics, myocardial function, and regional myocardial blood flow (MBF) were measured in 6 closed-chest ponies anesthetized with ketamine hydrochloride before (control) and after creation of acute right ventricular systolic hypertension (RVSH) during normoxia and isocapnic hypoxia. The right ventricular (RV) systolic pressure during each RVSH approached 90 mmHg. There were significant alterations in the pattern of total ventricular MBG distribution in favor of the RV. Because RV myocardium received proportionate increments to its endocardium as well as epicardium, it is concluded that autoregulation in the RV coronary vascular bed had not been abolished even during hypoxia + RVSH. Marked increase in MBF to the right side of the septum during each RVSH with little change in perfusion to other regions suggests that RV contraction is supported by the right side of the septum. Because these increments occurred with decreased RV coronary driving pressure they were the consequence of compensatory coronary vasodilatation. The slow heart rate of the pony in the presence of a large coronary vasodilatory reserve may have been the major factor in allowing large increments in MBF to the stressed regions despite decreased coronary driving pressure.


Acute cardiac ischemia and reperfusion: contractility, relaxation, and glycolysis. The mechanical and metabolic effects of 3 min of complete global ischemia and 25 min of reperfusion were studied in the isolated rat heart. The decrease in contracile function was biphasic; a rapid 50% decline occurred in the first 10 s of ischemia, after which contractile function transiently stabilized and then fell at a slower rate. During reperfusion, recovery of relaxation was impaired relative to recovery of contractile function. A second period of ischemia and reflow produced changes in contractility, relaxation, and lactate production virtually identical to the initial one. In the absence of glycolytic blockade, tissue lactate accumulation developed, no contracture occurred, the pacing threshold did not increase, and reperfusion after 3 min of ischemia resulted in complete recovery of contractile function. Glycolytic blockade with 0.1 mM iodoacetate (IAA) prevented ischemic lactate production, accelerated the fall in contractility, caused irreversible contracture after 30 s of ischemia, an irreversible increase in pacing threshold within 3 min of ischemia, and poor recovery of contractile function with reperfusion. Thus during the first 3 min of severe ischemia, glycolysis exerted a net beneficial effect on myocardial function despite significant tissue lactate accumulation.


Accentuation of heart sounds in anemia: an effect of blood viscosity. The effect of blood viscosity on the intensity of heart sounds was investigated in 25 anemic patients and 41 control subjects. Calibrated phonocardiograms showed that in anemic patients, the aortic component of the second sound was of greater amplitude (54 +/- 3 vs. 33 +/- 3 dyn/cm2) (P less than 0.001). The pulmonary component of the second sound and the first sound were also of higher amplitude in anemic patients (both P less than 0.001). The viscosity of blood of anemic patients was lower (0.029 +/- 0.001 vs. 0.045 +/- 0.001 poise) (P less than 0.001). Blood pressure was comparable among the two groups. Sound produced by closure of a normal porcine valve in an in vitro flow system also showed an accentuated sound with liquids of lower viscosity. Augmented diastolic vibrations of the closed valve, shown by high-speed motion pictures, accompanied the accentuated sound. These observations suggest that the accentuated second sound in anemic patients results from the lower blood viscosity, which reduces the damping forces that act upon the semilunar valve as it vibrates after closure. The reduced damping would allow augmented vibrations that result in an accentuated sound.


Cardiac output, GFR, and renal excretion rates during maintained volume load in rats. The correlation among cardiac output (CO), glomerular filtration rate (GFR), fractional tubular sodium rejection (TFRNa), and renal excretion rates of water and salt was investigated during ischemic blood volume expansion in rats. Initially circulating blood volume was equilibrated isovolemically with a reservoir volume of 6% albumin solution equal to one-third the estimated blood volume. Later the equilibrated reservoir contents were infused intravenously. CO was measured by thermodilution, GFR by inulin clearance. Significant linear correlations existed between GFR and the rates of urine flow (r = 0.90), sodium excretion (r = 0.75) and potassium excretion (r = 0.76) that prevailed 5--10 min after a given GFR change. The increased GFR was highly correlated with CO (r = 0.94), probably correlated with mean central venous pressure (r = 0.45), but not correlated with mean abdominal aortic blood pressure. The correlation between CO and time-delayed (5--10 min) TRFNa was also highly significant (r = 0.98). The saluresis appears to have been caused initially by increased tubular load and subsequently by decreased absolute tubular reabsorption.


Constituents of chyme responsible for postprandial intestinal hyperemia. While local venous outflow was measured in anesthetized dogs, various constituents of intestinal chyme were placed in the jejunal lumen to identify those responsible for postprandial intestinal hyperemia. Digested food and its supernatant increased local blood flow, whereas its precipitate, undigested food, and pancreatic enzymes did not. In the jejunum bile alone had no effect, but it markedly enhanced the hyperemic effect of digested food. Bile in the ileal lumen, however, increased local blood flow. At physiological postprandial concentrations in the jejunum, glucose, and micellar solutions of oleic acid and monoolein increased flow, but taurocholate and 16 common dietary amino acids did not. The hyperemic effect of lipids required the presence of taurocholate. Of the 16 amino acids, only Glu and Asp increased flow at 10 times the physiological concentrations (28 and 20 mM, respectively). The study indicates that the constituents of chyme responsible for postprandial intestinal hyperemia are the hydrolytic products of food, especially those of carbohydrates and fats and that bile plays an important role in the hyperemia.


Effects of adenosine on intestinal hemodynamics, oxygen delivery, and capillary fluid exchange. Systemic arterial pressure, superior mesenteric arterial and venous pressures, blood flow, arteriovenous oxygen difference, lymph flow, and intestinal volume were monitored continuously from an autoperfused loop of cat ileum to determine the effects of locally infused adenosine on intestinal hemodynamics, oxygen consumption, and capillary fluid exchange. The results indicate that adenosine, inosine, and hypoxanthine are vasodilators in the intestinal circulation. Local infusion of adenosine significantly reduces vascular resistance, but lymph flow, lymph oncotic pressure, and lymphatic protein flux remained unchanged from control, and the intestinal volume rapidly became constant after an initial blood volume shift. Intestinal oxygen consumption decreased significantly in both autoperfused and constant flow preparations. Pretreatment with aminophylline prevented the reduction in oxygen consumption and greatly attenuated the vasodilatory effect of adenosine. The reactive hyperemic response to 60-s arterial occlusions was virtually unchanged following aminophylline treatment. Adenosine depressed oxygen utilization of mucosal and muscularis strips in vitro and caused a significant redistribution of blood flow from the mucosal-submucosal layer to the muscularis in autoperfused preparations. The results of this study indicate that adenosine significantly reduces vascular resistance and oxygen consumption, yet does not alter fluid exchange in the small intestine.


Effects of acute global ischemia on diastolic relaxation in canine hearts. It is not known whether ventricular relaxation can be altered by ischemia independent of associated hemodynamic changes. The effect of acute myocardial ischemia on diastolic relaxation was studied under controlled hemodynamic conditions in 16 anesthetized dogs on right-heart bypass. In nine dogs, left ventricular end-diastolic pressure was maintained constant throughout the experiments. Ischemia produced a significant prolongation of the isovolumetric relaxation period (IVRP) from 29 +/- 3 (SE) to 88 +/- 7 ms (P less than 0.01). Ischemia, per se, the associated decrease in contractility, or the fall in peak left ventricular pressure (LVP) may have contributed to the increase in IVRP. The latter was not the only mechanism involved, because in seven dogs studied with constant peak LVP, IVRP again was prolonged from 64 +/- 8 to 95 +/- 8 ms (P less than 0.01). Moreover, in five nonischemic hearts in which peak LVP was maintained constant, contractility was decreased by sodium pentobarbital to the same extent as with ischemia; IVRP did not change. Thus, the additional prolongation of the IVRP in the ischemia experiments is secondary to a direct effect of ischemia on the relaxation process of the myocardium.


Survival and microvascular responses to hemorrhage with three anesthetic combinations. The effects of different anesthetic combinations on the responses to hemorrhage were investigated while using a single fixed protocol. Small artery (x +/- SE = 112 +/- 3 micron)) and vein (172 +/- 5 micron) responses to hemorrhage were quantitated in the cremaster muscle of 38 Sprague-Dawley rats via closed-circuit television microscopy. Rats were anesthetized intraperitoneally with pentobarbital (50 mg/kg), urethan (800 mg/kg), and alpha-chloralose (60 mg/kg), or urethan (600 mg/kg) and alpha-chloralose (120 mg/kg). After a 15-min control period, arterial blood pressure was lowered to 30 mmHg and maintained at that level for 60 min via hemorrhage from the femoral artery. The hemorrhaged blood was then reinfused, and recovery was monitored for 30 min. Survival was monitored for 7 days. Rats with heavier body weights (greater than or equal to 160 g) had a significantly greater survival rate, 81%, than did the lighter weight rats (less than 160 g), with a 32% survival rate. There were, however, no statistical differences in survival or microvascular responses among rats anesthetized with the three combinations of anesthetics. The combined data for all rats were: survival, 53%; small artery constriction, 45 +/- 2%; and small vein constriction, 21 +/- 3%.


Reflex circulatory changes due to the afferent stimulation of cat pericoronary nerve. Two different types of circulatory reflexes evoked by electrical stimulation of afferent fibers in the left pericoronary nerves were studied in anesthetized cats. A depressor response (-32.5 mmHg) with bradycardia (-48.7 beats/min) in 21 of 31 cats was mediated by the C fibers in the right vagal cardiac nerve trunk. The efferent pathway for the bradycardia was in caudal cardiac branches of the right vagus. Neither sympathetic denervation to the heart nor atropine attenuated the hypotensive response significantly, suggesting that the depressor response results from reflex inhibition of peripheral sympathetic activity. A pressor reflex without heart rate change was observed either when the vagi were blocked or when the distribution of vagal afferents in the pericoronary nerve was considered to be small. The pressor reflex was mainly mediated by the afferent C fibers within the left cardiac sympathetic nerves. The depressor response was enhanced by sympathectomy, suggesting the sympathetic counteraction on the inhibitory vagal afferents, Similarly, an enhancement of the pressor reflex by vagal blockade was observed, indicating tonic vagal restraint on excitatory sympathetic reflexes.


Ventricular performance and myocardial water content during hemodilution in dogs. In dogs anesthetized with chloralose-urethan on right heart bypass, left ventricular (LV) performance was assessed at constant LV stroke work before and for up to 2.5 h after crystalloid hemodilution was established. Lowering the hematocrit from 43.3 +/- 1.3% to 13.6 +/- 1.7% (SE) did not significantly change LV end-diastolic pressure (LVEDP) initially. After 80 min LVEDP increased slightly by 1.7 +/- 0.6 cmH2O (P less than 0.05) at a stroke work of 17.3 +/- 2.3 g.m. The value of dP/dt did not change significantly throughout. When LV function curves were generated by increasing cardiac output, the stroke work attained at an LVEDP of 10 cmH2O decreased with hemodilution from 23.9 +/- 3.5 to 20.8 +/- 3.9 g.m (NS). LV wall water content increased with hemodilution, from which it could be calculated that there was an 18.6% increase in LV mass. Thus, despite an increase in LV external girth demonstrated by LV circumferential gauges, it is possible that increased wall thickness due to the water gain resulted in little change or an actual decrease in LV end-diastolic volume. Thus, profound hemodilution can be attained with only slight depression of LV performance.


Analysis of myocardial and total body integral extraction ratios of rubidium-86. Coronary blood flow (QM) measurement with radiorubidium (Rb) assumes that Rb distributes to the myocardium in proportion to flow. This assumption is correct if the integral myocardial Rb extraction ratio (ERM) equals total body extraction (ERTB). A right-heart-bypass preparation was employed to test the hypothesis that ERM = ERTB and to examine the determinants of Rb extraction. Dogs were anesthetized with pentobarbital, and arterial, coronary venous, and total body venous Rb concentrations were continuously measured for 4 min after injection. We found that ERM (0.56 +/- 0.01) was significantly less than ERTB (0.70 +/- 0.01), P less than 0.01 (n = 29) and concluded that Rb did not distribute in proportion to flow. We do not recommend this method for clinical use. ERM is flow dependent and ERRB is a function of the total cardiac output and the distribution of cardiac output. Before employing Rb in animal experiments, it is recommended that a preliminary study be performed comparing flow measured with Rb to an independent measure of blood flow.


Release of norepinephrine by sympathetic nerve stimulation from rabbit lungs. Rabbit lungs were perfused via the pulmonary artery and norepinephrine (NE) measured in the outflows. The basal NE level was approximately 3 ng/min. Electrical stimulation (50 V, 1 ms, 10 Hz) of the sympathetic nerves doubled the NE release. Hexamethonium (10(-4) and 10(-5) M) had no effect on the release of NE. Administration of a monoamine oxidase (MAO) inhibitor, pargyline (70 mg/kg) resulted in a 20-fold NE increase by nerve stimulation, implying that the bulk of the amine does not reach the systemic circulation due to an active MAO. Methacholine (1 and 10 micrograms/ml) inhibited NE release by nerve stimulation. This inhibition was abolished by atropine (5 micrograms/ml). It is suggested that a muscarinic inhibitory mechanism may regulate the NE release in the lung. PGE2 (100 ng/ml), but not PGS2alpha, (100 ng/ml), depressed NE release during nerve stimulation, whereas indomethacin (10 mg/kg) enhanced NE release before, during, and after nerve stimulation in seemingly normal animals. This indicates the existence of another presynaptic inhibitory mechanism for NE release in the lung: a PGE-mediated inhibition.


Heterogeneity of oxygen delivery in normoxic and hypoxic states: a fluorometer study. An on-line, real-time histogram display of heterogeneity of oxygen delivery to perfused and in situ organs is afforded by a flying-spot fluorometer that provides excitation for either oxidized flavoprotein of the mitochondrial space or reduced pyridine nucleotide of mitochondrial and cytosolic spaces. Emission from the two fluorochromes is acquired at 10(4) to 10(5) data points/s and histograms of the fluorescence intensity versus the number of occurrences of that intensity are displayed at 1--10 times per second. The histograms show alterations of the intensity and of the degree of heterogeneity of the redox states of perfused heart with model coronary occlusion, of perfused and in situ rat liver, and of rat and gerbil models of stroke. The percentage change of oxygen delivery to the intracellular space can be calculated from the areas under the histogram.


Skin color, ethnicity, and blood pressure I: Detroit blacks. Census areas in Detroit were ranked for their stress scores based on instability (e.g., crime, marital break up) and socioeconomic status. Four areas were selected for detailed study: 1) high stress, population predominantly black, 2) white, 3) low stress, population predominantly black, 4) white. A sample was drawn from each area of persons of the predominant race, 25-60 years old, married and living with spouse, and having relatives in the Detroit Area. Nurses interviewed such persons; three blood pressure readings were taken during the first half-hour of medical history, and skin color was rated. Results show that darker skin color, for black males especially, is related to higher pressure, independently of nine control variables (e.g., age, weight, socioeconomic status, etc.). However, younger black males (25-39 years of age) in high stress areas had higher pressure than counterparts in low stress areas, regardless of skin color and relative weight; for older black males (40-59 years of age) darker skin color was correlated with higher pressure, regardless of relative weight or stress area. For 35 blacks whose fathers were from the West Indies, pressures were higher than those with American-born fathers. These findings suggest that varied gene mixtures may be related to blood pressure levels and that skin color, an indicator of possible metabolic significance, combines with socially induced stress to induce higher blood pressures in lower class American blacks.


Skin color, ethnicity, and blood pressure II: Detroit whites. Census areas in Detroit were ranked for their stress scores based on instability (e.g., crime, marital break up) and socioeconomic status. Four areas were selected for detailed study: 1) high stress, population predominantly black and 2) white, and 3) low stress, population predominantly black and 4) white. A sample was drawn from each area of persons of the predominant race, 25-60 years old, married and living with spouse, and having relatives in the Detroit Area. Nurses interviewed such persons; three blood pressure readings were taken during the first half-hour of medical history, and skin color was rated. While lighter skin color showed a negligible relation to higher blood pressure, a four-category division of European national background based on a skin color cline in Europe from Northern areas to the Mediterranean was significantly associated with a nurse-rating of skin color. The rank order of this four category variable, white ethnicity, was related linearly to both systolic and diastolic blood pressure means. Respondents with parents from Mediterranean countries had the lowest pressures and those from Northern Europe had the highest. The relationship is stronger for women than men. The relationship was independent of nine other control variables including age, overweight, smoking etc., and high and low stress areas, although of greater magnitude for the high than low stress groups. In this article, findings in whites are compared with prior results in blacks. Findings suggest that physiological and biological correlates exist that can be explored profitably by future research.


Aquatic vegetation and water pollution control: public health implications. Results obtained from pilot studies and the operation of a plant scale treatment facility located at the Williamson Creek Wastewater Treatment Plant at Austin, Texas, demonstrate that culture of the water hyacinth Eichhornia crassipes in shallow earthen basins is effective in the removal of algae, fecal coliform bacteria dn deleterious impurities from wastewater stabilization pond effluent. Stabilization ponds followed by hyacinth culture constitute an economical, low energy treatment system which reduces significantly those potential health hazards associated with wastewaters. Harvested hyacinths represent a useful product which could be converted into compost, or used directly as a soil amendment.


Long-term effects of a cancer awareness program for community pharmacists. A continuing education program resulted in a 52% improvement in the specified professional behaviors of community pharmacists within one month. However, surveyed effects were not permanent and decreased significantly within 18 months. Following a simple mailing of specially designed literature, desired behaviors again underwent significant improvement comparable to that attributed to the original continuing education program. A better understanding of professional behaviors as functions of time and different educational modes would be invaluable to educators in both academic and postgraduate programs.


Traumatic lesions of the metatarsophalangeal joint of the great toe in athletes. In the 1972, 1973, and 1974 football seasons at the University of Arkansas, 74 players sustained sprains of the ankle, producing a total of 152 missed practices and 6 missed games. Although only 18 injuries of the first metatarsophalangeal joint complex were seen, these later resulted in 92 missed practices and 7 missed games. This injury has been a significant problem for both the university and for most other major institutions, judging from a 70% response to 94 questionnaires sent to trainers of 94 large colleges and universities throughout the United States. It is the researchers opinion that the artificial turf surface, particularly as it ages, the shoes, and shoe fitting are all possible contributors to the incidence of the problem. Nonoperative treatment, whose hallmark is rest, is the treatment of first choice. Taping and splinting with a 0.51-mm spring steel splint with reinforcement, both pre- and postinjury, are beneficial. Injections of steroids or any other attempt to return the still painful athlete to activity are contraindicated. Late surgery, particularly in the event of capsular ruptures, as well as early repair, can be of benefit. The need to re-evaluate the shoes and playing surfaces in the light of this and other injuries is emphasized.


The Cybex II evaluation of surgically repaired Achilles tendon ruptures. Thirty-two patients with 33 complete ruptures of the Achilles tendon with surgical repair were evaluated with the Cybex II isokinetic unit. The evaluations were performed from 6 to 144 months postoperatively. The repaired Achilles tendon had a 16.5% loss of plantarflexion strength and a 17.5% loss of plantarflexion power. The early repairs had a smaller loss of strength and power than late repairs. Twenty-seven of the patients returned to their former level of sports activity.


Shoulder dislocation in Swedish ice hockey players. 1. Humeroscapular dislocation, primary or recurrent, is found in 8% of elite ice hockey players in Sweden. 2. The dislocation recurs in 90% of greater than 20-year-old players and the frequency diminishes with increasing age. 3. The duration of immobilization after the first dislocation bears no sure relation to the risk of recurrence. 4. In 80% of the cases, the operated shoulder was the one that predominates in ice hockey, usually the left. Of the 32 operated players, 30 have been able to continue with ice hockey and relatively marked postoperative loss of mobility has been tolerated well. 5. Even without an operation, a recurrent shoulder dislocation did not prevent one-third of the players from continuing with ice hockey.


Injury potential in modern ice hockey.

Injury potential in modern ice hockey. The majority of the damaging forces to the soft tissue, bone, and articular joint structures of modern hockey players during the energetic activities involved in the game are attributable to impact action during high-speed motion. In addition, non-contact musculoligamentous injuries are common because of the complex forces that are involved. The injury potential of this sport is assessed indirectly from the force and motion involved. The experimental method of measuring the kinematic motion and the impact forces inherent to the sport are presented. Although hockey is a fast and furious game with high injury potential, fortunately the number of serious injuries is not as great as one might expect.


Patellar tendinitis (jumper's knee).

Patellar tendinitis (jumper's knee). A jumper's knee is an overload lesion of patellar or quadriceps tendon near its insertion at the lower or upper pole of the patella. If conservative treatment fails, an operation can be performed in Phase 3 where disabling symptoms, are present. The necrotic tissue in the patellar tendon is excised. The early results of this surgery are encouraging.


On the nature of stress fractures.

On the nature of stress fractures. It is felt that stress fractures are caused by excessive, repetitive muscle forces acting across the affected bone. These fractures should be suspected in participants of athletic endeavors who present with a history of persistent, focal, activity-related pain regardless of their stage of physical conditioning. Associated physical findings are localized tenderness and swelling without evidence of a generalized systemic response. Bone scans and serial roentgenograms including specialized views may be required for documentation. Limitation of the athletic activity is the hallmark of the treatment program.


Proliferative serous tumors of the ovary. Histologic features and prognosis. In reviewing all proliferative serous tumors of the ovary seen at Barnes Hospital from 1950 to 1974, we quantitated histologic characteristics and defined criteria for diagnosis in 55 borderline tumors, 13 well-differentiated cystadenocarcinomas, and 15 cystadenomas with unusual proliferative areas. This last type with focal proliferation behaved in a benign fashion and should be considered a variant of a simple cystadenoma. Stromal invasion was the only histologic feature which consistently distinguished carcinomas from the borderline tumors. The presence in some borderline tumors of severe cellular atypia, marked epithelial disorganization, frequent mitoses, and cribriform glands in the stroma neither signified carcinoma nor indicated poor prognosis. No patient with a Stage I borderline lesion died of tumor. Although the mortality of patients with Stage IIb or Stage III borderline tumors is high, tumor-related deaths rarely occurred before 5 years, and three patients lived more than 10 years. Borderline serous tumors are low-grade malignant neoplasms which differ from overt carcinomas in the excellent prognosis of Stage I lesions and in long survival even with widespread abdominal disease.


Jejunal perforation occurring in contact sports. Two cases of jejunal rupture following blunt trauma, occurring in participants of contact sports, have been reported. Additionally, a possible mechanism of injury is described.


Cystadenofibromas of the ovary with epithelial atypia. Epithelial atypia is rarely encountered in ovarian cystadenofibromas. Ten examples are reported with cytological features identical to serous tumors with low malignant potential. In two neoplasms the epithelium resembled an atypical endometrial hyperplasia, and one of these had squamous metaplasia. These two neoplasms probably qualify as endometrioid tumors of low malignant potential. None of the 10 patients had recurrence following excision of their neoplasm, and no similar patients have been encountered with neoplasms in more advanced stages. Even though aggressive behavior has not yet been established, the histologic features suggest a low degree of malignant potential and long-term follow-up of patients is warranted. Cystadenofibromas iwth epithelial atypia probably have less malignant potential than serous tumors of low malignant potential possessing the same epithelial characteristics because cystadenofibromas with atypia have less epithelial surface area and the epithelium is enveloped by connective tissue more than it is in serous tumors of low malignant potential.


Solitary (localized) pleural mesothelioma. A light- and electron-microscopic study. Six solitary (localized) pleural mesotheliomas were studied by light and electron microscopy. All the lesions were benign and were composed mainly of fibrous tissue of variable cellularity with or without cystic spaces lined by round cells. The lining cells of the cysts and the adjoining round plump cells were interpreted as true neoplastic cells of the fibroblast type. Results of light- and electron-microscopic study of human mesothelial cells and fetal mesothelial cells of rats were compared. The cytoplasmic organelles of the tumor cells were generally scanty, though rough endoplasmic reticulum, sparse mitochondria, intracellular bundles of fibrils, and numerous polysomes were seen. Some tumor cells had junctional apparatus and basement membrane and showed interdigitation of the plasma membrane. These cells lined the cystic spaces irregularly and also proliferated into the surrounding fibrous tissue, where they assumed a spindle shape and resembled fibroblasts. Ultrastructurally, the tumor cells were similar to mesothelial and stromal cells of fetal rat pleura. We speculated that the solitary (localized) mesotheliomas were probably derived from coelomic epithelium and that tumor cells remained undifferentiated or revealed minimal differentiation toward mesothelial cells.


Lymphoid hyperplasia of the gastrointestinal tract. A study of 26 cases and review of the literature. Based on a study of 26 cases and a review of the literature, lymphoid hyperplasia of the gastrointestinal tract can be categorized into four clinicopathologic groups: focal lymphoid hyperplasia of the stomach, focal lymphoid hyperplasia of the small intestine, focal lymphoid hyperplasia of the rectum, and nodular lymphoid hyperplasia of the gastrointestinal tract. The focal lesions are single, variably circumscribed, and produce thickening of the wall of the affected part of the viscus. While a substantial number of the gastric lesions are associated with chronic peptic ulcers, ulceration is absent or insignificant in focal lesions located in the intestine. The extent of the infiltrate may range from involvement of the mucosa and submucosa only to infiltration of the full thickness of the wall. Nodular lymphoid hyperplasia of the gastrointestinal tract produces multiple discrete mucosal nodules in a variable segment of the small intestine, large intestine, or both. Gastric involvement is rare. The lymphoid infiltrate is confined to the lamina propria and superficial submucosa. Nodular lymphoid hyperplasia is most commonly encountered incidentally during radiologic examination or at autopsy, but it also occurs in association with hypogammaglobulinemia, especially late-onset acquired hypogammaglobulinemia. Lymphoid hyperplasia of the gastrointestinal tract can be distinguished from malignant lymphoma by the polymorphic nature of the infiltrate, the absence of significant cytologic atypia, and the presence of reactive follicles within the lesion.


Ultrastructure of osteoclastoma-like giant cell tumor of thyroid. An aggressive anaplastic tumor of the thyroid with osteoclastoma-like giant cells was studied by electron microscopy. The lack of junctional complexes or other obvious epithelial elements suggested mesenchymal origin. The giant cells resembled osteoclasts with respect to mitochondria, rough endoplastic reticulum, lysosomes, ribosome complexes and vacuoles, but the prominent nuclear golgi apparatus of giant cell tumors of bone was absent.


Pulmonary blastoma evolving into carcinosarcoma. A case study. A rare lung tumor composed of contiguous foci of classical blastoma and carcinosarcoma with transitional features is described. Based on these observations and a review of the literature, we propose that pulmonary carcinosarcomas are composed of a heterogeneous population of tumors. This case supports the concept that blastomas are a distinctive subtype of carcinosarcomas. An unusual feature in the clinical presentation was the expectoration of an endobronchial portion of tumor.


Pulmonary blastoma. Report of two cases in children. Pulmonary blastoma is a rare tumor of the lung. Although it has been stated that this is predominantly a tumor of adults, a review of the 42 cases published to date reveals that it is a disease which occurs with some frequency in children. The tumor is relatively benign compared to pulmonary carcinosarcoma. Of the eight cases previously described in children, three are known to have survived and to be free of disease 10 months, 3 and 8 years after surgical resection. We report two additional cases of pulmonary blastoma in children followed for 34 and 26 months without any evidence of recurrence or metastases.


Enflurane nephrotoxicity and pre-existing renal dysfunction. This study provides the first morphological evidence of significant structural damage following high doses of enflurane alone and confirms previous findings of transient renal functional abnormalities following high dosage enflurane. The study also indicates that enflurane may have a greater potential for renal toxicity in the presence of renal impairment. Treatment of Fischer 344 rats with a nephrotoxic dose of gentamicin prior to six hours of enflurane (GE) anaesthesia at 1 MAC resulted in increased serum concentration of the enflurance metabolite inorganic fluoride (GE, 43.9 +/- 1.5; E, 34.5 +/- 1.8 mu mol/L), increased urine flow rate and a greater degree of structural damage in renal proximal convoluted tubule cells than was observed with either gentamicin (G) or enflurane (E) alone. Treatment with gentamicin prior to enflurane also resulted in reduced urinary osmolality compared to enflurane or gentamicin alone (GE, 742 +/- 57; E, 1709 +/- 66; G, 985 +/- 32 m0sm/kg).


Local cerebral blood flow and the electrocorticogram during sodium nitroprusside hypotension. Changes in local cerebral blood flow during sodium nitroprusside hypotension were measured using the hydrogen electrode technique. At mean arterial pressures from 90% to 50% of control values, local cerebral blood flow showed a significant decrease by 20%. When blood pressure was reduced below 50%, the local cerebral blood flow increased significantly and approached control levels. It is suggested that the flow increase may be due to local hypoxia. Associated with this increase were electrocorticogram changes indicative of hypoxia. The significant decrease in mean local cerebral blood flow and the large range of flows seen during mild hypotension indicate that autoregulation is impaired. During hypotension, intracranial pressure increased by, at most, 3 mm Hg. Cardiac output was usually unaffected and was never decreased by more than 20%.


The surgical diathermy: principles of operation and safe use. An understanding of the principles of operation and hazards of the surgical diathermy is necessary for the safety of the anaesthetized patient. The surgical diathermy performs its function by the application of high density radio frequency current which can be used to cut or coagulate tissue. Its improper use can result in electrical burns and even electrocution. The principles underlying its safe use are outlined, and detailed recommendations are made to ensure the patient's safety.


Mechanism of the hypertensive effect of droperidol in pheochromocytoma. Droperidol is used in the anaesthetic management of pheochromocytoma because of its sedative, anti-dysrhythmic and alpha-adrenoreceptor blocking properties. However, droperidol when used in pheochromocytoma, has been reported to produce a paradoxical hypertensive response. In vitro experiments with perfused rabbit ear arteries using a histochemical fluorescence technique, showed droperidol to be an inhibitor of noradrenaline uptake into sympathetic nerve endings, and this uptake inhibition was dose related. The uptake inhibition effect did not, however, produce pressor changes in experiments simulating pheochromocytoma in cats. The hypertensive response to droperidol may be due to blockade of presynaptic alpha-adrenoreceptors and this possible mechanism of action is discussed.


Topical cocaine/adrenaline combination in intransal surgery--is it necessary? Topic adrenaline with cocaine has been used commonly for intranasal vasoconstriction to facilitate surgery and to control haemorrhage. Pharmacologically the drug combination is known to be a potentially dangerous interaction. This investigation studied whether either drug could be used separately rather than in combination, to achieve the same purposes. One hundred cases were randomized into four groups using 1:1000 Adrenaline, 5% Cocaine, 10% Cocaine and 5% Cocaine/1:1000 Adrenaline as the topical vasoconstriction regimes. The results showed that the vasoconstrictor effect was not significantly different within the four groups; topical 1:1000 Adrenaline resulted in more haemorrhage compared to the other three regimes; comparing the other three regimes the blood loss was not significantly different. The conclusion is that the Adrenaline/Cocaine mixture has no advantage and its potentially dangerous interaction makes it unnecessary and unjustified. Topical 5% Cocaine is recommended because it achieves the aims with the least side-effects.


Effects of etomidate given in repeated doses. Fifty fit, female patients were given four consecutive intravenous doses of etomidate 10 mg, so as to maintain sleep, after establishment of epidural block for postpartum sterilization. A matched group was given four doses of thiopentone 125 mg. Cumulative hypnotic effect, as judged by increasing sleep duration with second and subsequent doses, was much less with etomidate than with thiopentone. Etomidate did not depress blood pressure, whereas it fell progressively with successive doses of thiopentone. Injection pain was reported in 68% of patients receiving etomidate, and this tended to increase with successive doses; 12% also showed local inflammation at the injection site. Tremor, due to etomidate, was common, but did not increase with successive doses. Feelings of sleepiness, lasting several hours after waking, were more common after thiopentone than after etomidate.


Ultrastructure of developing alveoli. I. The role of the interstitial fibroblast. We examined the ultrastructural features of postnatal alveolar septal formation in rats from birth to 28 days of age. At birth, the rat lung consists of large saccules with thick walls and cellular interstitium. Interstitial cells have large oval nuclei with scant cytoplasm containing few organelles and scattered lipid droplets. These cells appear to be poorly differentiated mesenchymal cells not engaged in active protein synthesis or secretion. Between 5 and 15 days of age, saccule walls thin and many new alveolar septa form. Two types of interstitial fibroblasts are present: one which appears at the tips of newly formed septa has the characteristics of a myofibroblast and appears to be engaged in synthesis and secretion of elastin; the other fibroblast appears at the base of new septa, is filled with lipid and contains few other cytoplasmic organelles. After 15 days of age, alveolar walls become thinner, few new septa form and interstitial fibroblasts begin to resemble the dormant type of fibroblasts seen at birth. Thus, the process of postnatal alveolarization of lung parenchyma involves differentiation of the interstitial fibroblast and elastogenesis. The factors which control this process, the precise role of elastogenesis in alveolar septal formation, the origin and fate of the lipid filled fibroblast and the ultimate fate of the myofibroblast remain to be determined.


Unusual features of the nuclear envelope in human spermatogenic cells. Different types of human germ cells show unusual features of the nuclear envelope. Spermatogonial nuclei demonstrate two kinds of modifications. The first one is a series of intranuclear flattened cisterns, parallel to each other and to the inner aspect of the nuclear envelope. The second one is a nuclear envelope protrusion into the cytoplasm occupied by a double membrane-limited vesicle. Pores are found on the membrane of the vesicle facing the interior of the nucleus. In spermatocytes the nuclear pores are concentrated over certain areas and completely absent from others. In the regions where they are absent a single cytoplasmic cistern of rough endoplasmic reticulum is closely apposed to the outer membrane of the nuclear envelope. Early modifications of the nuclear surface appear in spermatids before the attachment of the acrosomic vesicle and may indicate an active role of the nuclear envelope in the morphogenesis of the acrosome. In round spermatids nuclear pores are absent from the area which is first related to the Golgi and later covered by the acrosomal cap. Single or multiple layers of cytoplasmic annulate lamellae are closely associated with the nuclear envelope over the pore rich areas. Frequently there are intranuclear accumulations of dense material adjacent to the annulate lamellae-nuclear pore complex. The chromatoid body is usually present on the cytoplasmic side of this complex. In the elongating spermatids most annulate lamellae are free in the cytoplasm, often in relation with Golgi and chromatoid body remnants near the axial filament. Few stacks of annulate lamellae are noted adjacent to the pore rich nuclear regions. It is suggested that the described modifications are related to an active nuclear-cytoplasmic interaction.


Attrition of the human Leydig cell population with advancing age. Existing evidence suggests that the aging human male experiences a gradual decline in testosterone production, a phenomenon that should be reflected in the Leydig cell population of the testis. It has been proposed that Leydig cells diminish in number with increasing age, but conflicting claims characterize reports of this topic. We have reinvestigated this possibility by histometric analysis of perfused testes from 25 men ranging from 18 to 87 years of age. Average single Leydig cell volume (2,943 +/- 623 micrometer 3, X +/- S.D.) did not change significantly with increasing age (r = 0.24, P greater than 0.2), suggesting that surviving cells remain active. Total testis weight (43.5 +/- 13.9 g) also did not change with age (r = 0.04, P greater than 0.5). However, both total Leydig cell volume and the absolute number of Leydig cells per individual decreased significantly as functions of age (r = -0.71, P less than 0.002, and r = -0.61, P less than 0.005, respectively). Analysis of relationship between these two parameters indicates that the total volume of Leydig cell cytoplasm contained within the human testis is determined by the number of cells present. Our results show that a pair of young adult testes endowed with more than 700 million Leydig cells at 20 years of age may be expected to undergo an attrition rate of approximately 80 million cells per subsequent decade of life. Thus, Leydig cell attrition is an important correlate of declining androgen status in aging men.


Morphological and quantitative analysis of spermatogonia in mouse testes using whole mounted seminiferous tubules, I. The normal testes. The spermatogonial populations in ten normal adult mice were analyzed using whole mounted seminiferous tubules. The undifferentiated A spermatogonia as well as the six generations of differentiating spermatogonia were clearly identifiable on whole mounts. Description plus quantitation of these cell types revealed that they behaved in essentially the same manner as their counterparts in the rat. Single undifferentiated  A cells were classified as type As stem cell spermatogonia. They were distributed throughout the seminiferous epithelium, and by periodic mitoses, maintained their stock and furnished cells which would eventually differentiate. Although initially resembling the As spermatogonia, the progeny which were destined to differentiate were classified as type Aal spermatogonia because they were linked by cytoplasmic bridges, and because they usually underwent one or more synchronous mitotic divisions to form short chains of aligned cells. Ultimately, division of Aal cells were no longer seen, and the cells appeared to gradually acquire the typical morphological characteristics of A1 spermatogonia; these continued to differentiate according to the well-established pattern. It was concluded that the cyclic production of cohorts of A1 cells in this manner would ensure a continual supply of spermatogonia for differentiation.


Morphological and quantitative analysis of spermatogonia in mouse testes using whole mounted seminiferous tubules. II. The irradiated testes. In adult male mice exposed to 300 R X-irradiation, the spermatogonial population was selectively killed except for the radioresistant type As stem cells. Type A spermatogonia were minimal two days after irradiation, when only 20% of the control population was present in stage 5-6; these were predominately single and paired undifferentiated cells. When multiple injections of 3HTdR were given between 2 and 3.5 days post-irradiation, 90-95% of these survivors in stages 4-6 became labeled. Enhanced proliferation of these stem cells, and at times when they were normally quiescent, led to restoration of all classes of spermatogonia by 11 days after irradiation. Several autoradiographic studies were undertaken to better characterize the radioresistant cells. In mice given single or multiple injections of 3HTdR prior to irradiation, there was appreciable retention of label by those type As spermatogonia that had originally incorporated 3HTdR in stages 2-4. This labeling pattern was identical to that of the long-cycling As stem cells in nonirradiated testes. Since the long-cycling As stem cells are thought to be characterized by a prolonged G1 or "A-phase" which is known to be a highly radioresistant portion of the cell cycle, it was clear why these cells could preferentially survive irradiation doses that killed other spermatogonial types. It was proposed that following germ cell depletion, as after irradiation injury, the long-cycling As survivors could be prematurely triggered from A-phase into DNA synthesis, thereby, initiating restoration of the germ cell population.


The effects of 5alpha-reduced androgens on maintenance and regeneration of prostate glands and seminal vesicles in castrated and hypophysectomized rats. The effects of 5alpha-androstane-3alpha, 17beta-diol (3alpha-diol) and 5alpha-androstane-3beta, 17beta-diol (3beta-diol) were studied in rats hypophysectomized and treated daily for 30 days with the steroids, starting on the day of surgery (hypophysectomized, H) or 30 days following the removal of pituitary (hypophysectomized regressed, HR). The ability of 3beta-diol to maintain and restimulate the prostate glands and seminal vesicles of castrated (C) and castrated regressed (CR) rats, respectively, was also studied. This androgen (3beta-diol) was able to maintain as well as rejuvenate to some degree the sexual accessory glands of all treatment groups. The prostate glands and seminal vesicles in both castrated experimental groups showed increased stimulation with progressively higher dosages of 3beta-diol. At all dose levels, stimulation of seminal vesicles of CR rats was comparable to that of non-regressed castrates. The prostate glands, on the other hand, showed better maintenance in the higher dosage group. In H rats, the stimulation of sexual accessory glands by both androgens was not significantly different than normal controls. The seminal vesicles and prostate glands of HR rats treated with 3alpha-diol were well stimulated and comparable to those of H rats treated with 3alpha-diol. The seminal vesicles of HR rats treated with 3beta-diol were also well stimulated, though not to the extent as those with 3alpha-diol treatment. The prostate glands of the 3beta-diol treated HR rats were significantly smaller than those of the 3alpha-diol treatment group. However, these miniature glands were morphologically stimulated as evidenced by mitosis of parenchymal cells and accumulation of secretory products in the alveoli. This study clearly indicates that 3beta-diol is biologically active and the degree of stimulation varies with the animal preparation in which the androgens were tested.


Effects of testosterone enanthate on the structure of the male reproductive tract of the rat. The histology and fine structure of the testis, epididymis and sex accessory glands were studied in young adult male rats administered testosterone enanthate, 120 microgram/100 g body weight, three times weekly for 4, 8, or 12 weeks. The weights of the testis and epididymis decreased, and animals treated for 11 weeks were infertile. Alterations were found in the seminiferous tubules of all rats treated for 8 or 12 weeks, including the presence of many degenerating germ cells and a large decrease or absence of late spermatids. Study of different stages of the cycle of the seminiferous epithelium showed that the greatest number of degenerating germ cells, step 7 spermatids and pachytene primary spermatocytes, occurred at stages VII-VIII of the cycle. Some normal appearing spermatogonia, primary spermatocytes and early spermatids remained in most seminiferous tubules. Sertoli cells contained many lipid droplets and lysosome-like bodies, and degenerating cells were surrounded by Sertoli cell cytoplasm. The Leydig cells of treated animals were greatly reduced in size. Sperm progressively disappeared from the lumen of the middle segment and proximal part of the terminal segment of the epididymis after treatment for 8 or 12 weeks. Changes in the middle segment also included the appearance of intraepithelial cavities containing debris, and the presence within the epithelium of phagocytic cells that resembled leukocytes. The lumen of the proximal part of the terminal segment was often collapsed, while in the distal part of the terminal segment, the lumen was filled with cellular debris and degenerating sperm. Organelles of the principal cells of the epididymal epithelium appeared to be qualitatively unaltered. The weight of the sex accessory glands remained close to normal, and the presence of normal ultrastructural features suggested that production of secretions continued.


Clinical experience with an alloplastic spermatocele. During the last 4 years we succeeded in proving in experiments in rats and bulls that a cup-shaped silicone-dacron prosthesis may be used as Sperm-reservoir. Spermatozoa--aspirated from this reservoir and stored as pellets in liquid nitrogen over 6 weeks--induced pregnancies and normal births in 50 percent of inseminated cows. Because of aplasia or long stenosis of the vas deferens 26 prostheses (20 X 8 X 8 mm) were implanted upon the epididymis in 14 patients. Percutaneous aspirations up to 7 months after operation showed up to 105 million spermatozoa persingle aspiration. The number and the motility of the aspirated spermatozoa varied considerably from one puncture to the next. Quality and quantity of spermatozoa decreases in correlation with longer postoperative delays. Average aspiration-time was 3 months and positive sperm counts were obtained on an average for 2 months. Insemination of the patients' wives with the aspirate did not result in any pregnancy so far. In "hopeless cases" presenting excretory azoospermia and aplasia or long stenosis of the vas, we try to obtain maximal numbers of spermatozoa by early and frequent aspiration of the implanted alloplastic reservoir for well "timed" direct insemination and deepfreezing.


Effect of various prostaglandins on the metabolism of fructose by epididymal and ejaculated ram spermatozoa in vitro. The effects of a number of prostaglandins on the metabolism of fructose by epididymal and ejaculated ram spermatozoa were investigated using conventional Warburg techniques. Spermatozoa from the two sources were collected concurrently during electrical stimulation; the epididymal spermatozoa were harvested via a cannula inserted chronically into one vas deferens and thus were free from exposure to the seminal prostaglandins. In general, the metabolism of fructose by the spermatozoa was little affected by a wide range of prostaglandins at a concentration of 20 micrograms/ml. Of the PGs present in semen, PGE2, PGE3 and PGF2alpha had no significant effects whereas PGE1 and PGF1alpha significantly increased lactate accumulation and the latter increased oxygen uptake, in both cases without significantly changing fructose utilization, fructose oxidized or CO2 production. Both 15-methyl-substituted PGE2 and PGF2alpha and their corresponding methyl esters failed to change fructose metabolism and it is unlikely therefore that the lack of response to PGE2 and PGF2alpha was due to their being metabolized by the spermatozoa during the incubation. Of a number of breakdown products tested, PGA1 and to a lesser extent PGA2 appeared to inhibit the Krebs tricarbocyclic acid cycle and 15-keto 13,14-dihydro-PGF2alpha appeared to stimulate it. In general, epididymal spermatozoa responded to the PGs in the same way as ejaculated spermatozoa. Thus we did not confirm a suggestion in the literature that spermatozoa have lowered sensitivity to PGs in vitro once they have been in contact with the PGs in seminal plasma.


Seminal fructose, citric acid and acid phosphatase before and after vasectomy in man. Seminal fructose, citric acid and acid phosphatase were estimated from 23 healthy males before vasectomy and three months later. Each subject had children and the men volunteered for sterilization because other possibilities of contraception were inapplicable. Vasectomy was performed under local anesthesia in the conventional manner. Semen of all patients was azoospermic three months after vasectomy. In this study, the amounts of seminal fructose and citric acid were significantly higher after vasectomy than before operation. The activity of seminal acid phosphatase was a little less, but the difference was not significant. The increase of seminal fructose and citric acid could be explained by the lack of spermatozoa, which normally use them into their metabolism.


A new anesthesia delivery system.

A new anesthesia delivery system. A prototype anesthesia delivery system has been developed to test the appropriateness of new technological design approaches. The objectives were to eliminate human-factors problems associated with present anesthesia apparatus and to lay a suitable technical foundation for the development of new techniques in anesthesia management. This prototype performs all the functions of a conventional anesthesia machine, as well as many monitoring and surveillance tasks. Eventual incorporation of new teaching functions, and additional monitoring and record-keeping activities, are intended. The system is fundamentally electronic with few moving parts. Reliability, safety, and clarity of operation were the primary criteria in selection and application of the specific technologies employed. The result is a promising first step in the development of a system oriented toward supporting rather than preoccupying the anesthestist.


Positive feedback of gonadotropins in males. The influence of estradiol and progesterone upon serum LH and FSH has been evaluated in three groups of five normal adult males. These steroids were administered to ascertain whether the hypothalamus and pituitary in the male possesses the capability for acute release and positive feedback of gonadotropins, a well established characteristic of the hypothalamus and pituitary in the female. Suppression of circulating levels of gonadotropins occurred after the oral administration of 0.1 mg of ethinyl estradiol daily for three days to experimental group 1, and after 0.1 mg ethinyl estradiol given daily for nine days plus 1.0 mg given on day 10 to experimental group 2. Positive feedback of serum LH levels occurred in two of five men of experimental group 3 after they received 0.5 mg ethinyl estradiol orally daily for three days. Three men had a rise of FSH concentration between day 5 and 8 of the administration of this drug. Ten mg of progesterone (IM) given to these men after suppression with estradiol also produced a positive feedback of FSH in three and of LH in four of the five men.


Pharmacokinetics and pharmacodynamics of d-tubocurarine during hypothermia in the cat. To determine the effects of hypothermia on the pharmacokinetics and pharmacodynamics of d-tubocurarine (dTc), serum, biliary, and urinary concentrations were determined and twitch tension monitored following intravenous administration of dTc, 0.7 mg/kg, at 39 (n = 5), 34 (n = 5), and 28 C (n = 6) in cats anesthetized with chloralose and urethane. Time from injection of dTc to maximum neuromuscular blockade was prolonged by hypothermia (28 C). Similarly, moderate (28 C) but not mild (34 C) hypothermia delayed recovery from paralysis. The serum half-life was prolonged 76% and the serum clearance rate decreased 60% by hypothermia (28 C). The combined biliary and urinary elimination of dTc was decreased 47% at 28 C compared with 34 and 39 C. The serum concentration of dTc necessary for neuromuscular blockade was less at 39 C (ED50 0.87 microgram/ml) than at 34 or 28 C (ED50 1.13 microgram/ml). It is concluded that, in vivo, hypothermia antagonizes a dTc-induced neuromuscular blockade but decreases the elimination of dTc. At 28 C the net effect is a prolongation of neuromuscular blockade.


Effects on rabbit spermatogenesis following orthostatic collapse. Light microscope qualitative and quantitative studies. Forty rabbits were submitted to orthostatic collapse, divided into 9 groups and sacrificed 6, 12, 24, and 48 hours, 4, 7, 15, 30 and 45 days following collapse. Ten animals were used as controls. The testis and epididymis were submitted to microscopic examination. The most striking change was necrosis of seminiferous cells which was most severe in the 24-hour group. The most susceptible cell to necrosis was the primary spermatocyte whilst spermatogonia, Sertoli cells and Leydig cells were not damaged. Other frequent changes included hypertrophic spermatocytes, hypertrophic early spermatids, nonelongated late spermatids, nonelongated multinucleated late spermatids, multinucleated and binucleated early spermatids. A quantitative study done by counting tubular cross-sections with presence of the changes described showed a significant increase of frequency in the rabbits submitted to orthostatic collapse. The histological changes can be related primarily to the circulatory disturbance leading to oligaemia and consequently to anoxia and are strikingly similar to those following experimental ischemia of testis.


[Free fatty acid composition of human semen in different clinical diagnoses]. The composition of free fatty acids of human semen from different clinical diagnosis was determined by gas liquid chromatography. The major components were palmitic, stearic, myristic and oleic acid. The analyses indicate that the percentage composition of palmitic acid was distinctly lower in the group with azoospermia.


[Experimental studies on the reaction of the vas deferens to different traumata]. In animal experiments the reaction of the ductus deferens to various traumata was studied. The investigations performed on 115 rats were to clarify the following problems: 1. Can a transient trauma, as occurring during preparation or roentgenographic visualization, cause a luminal obstruction? 2. How can vasectomy be done safely in such a manner that chances for a later vasovasotomy are not reduced more than necessary? The findings permit the following conclusions: 1. The surgical exposure of the ductus deferens as well as the checking of its permeability by means of x-ray contrast medium do not lead to a luminal obliteration when performed appropriately under surgical conditions in the course of a vasovasotomy. 2. Sterilization is achieved by partial vasoresection combined with intravasal fulguration. However, the ductus deferens remains understroyed not far from the defect; therefore, after resection of the scarred area a vasovasostomy would still be successful.


The relationship between plasma FSH, testosterone levels and testicular histology in males with azoospermia. The plasma FSH and testosterone levels were determined by the radioimmunological method in 27 men with azoospermia. The plasma FSH levels were elevated in the Sertoli-cell only syndrome and in the case of inhibited spermatogenesis. The plasma FSH level was normal in patients with normal spermatogenesis. The plasma testosterone level did not differ from the normal values in any of the above-mentioned groups of patients.


Epididymal sperm reserve in Buffalo-bulls (Bubalus bubalis). Epididymal sperm reserve was determined in 6 sexually mature fertile buffalo-bulls having normal process of spermatogenesis. The relative distribution of spermatozoa in the caput, corpus and cauda epididymidis averaged 5.42, 0.75 and 11.45 billion respectively. Total epididymal sperm reserve per bull averaged 36.2 billion. In terms of percentage the caput, corpus and cauda epididymidis contained 30.76, 4.25 and 64.99 per cent sperm respectively.


[Contribution on the parasite fauna of the GDR. 2. Studies of the incidence of helminths in roe-deer (Capreolus capreolus)]. The authors show the results of researches on the helminthofauna in roe deers from two different hunting-grounds. The results are compared with those of other authors in GDR and the Central European region. In roe deers 37 different helminths--1 species of Trematoda, 3 species of Cestoda and 33 species of Nematoda--are found up to till now in GDR. Finally some informations are given about the extense- and the intense-infection of the hosts.


[Developmental cycle of Stomylotrema vicarium]. With metacercariae encysted naturally in the visceral cavity of Megadytes glauca-larvae (Dityscidae), day old unfed chicken and a Belonopterus cayennensis were infected and adults of Stomylotrema vicarium Braun, 1901 obtained. Metacercariae and adults have an excretory bladder with lateral ramifications and 4 groups of 10, exceptionally 12 flame cells on each body side. Very young metacercariae without cysts presented a big stylet. A corresponding virgula-cercaria in Ampullaria canaliculata is supposed.


[Massive infestation of Goniocotes megalocephalus on an injured hazel-cock]. A strong infestation of Goniocotes megalocephalus [Mallophaga] on the adult male of Hazelgrouse (Tetrastes bonasia rupestris C. L.Brehm, 1831), which died gradually in cause of a trauma, is described. The result of examination and circumstances of it are dicussed. The poor condition of the bird caused by the trauma and its reduced activity during the winter season were probably the most important factors, on account of these the population of the parasites was increased.


[Influence of the hematocrit on the formation of Heinz bodies within the red cells (author's transl)]. The increased in vitro formation of Heinz bodies in erythrocytes exposed to oxidant agents (acetylphenylhydrazine) is an excellent screening test for the diagnosis of various congenital abnormalities of red blood cells (G-6-PD deficiency, unstable haemoglobins). This phenomenon is strongly dependent of the PCV of the test blood. Anemia by itself (hematocrit less than 30 p. cent) may be responsible for an increased formation of Heinz bodies even in the absence of any erythrocyte abnormality. This finding confirm that the results of the test are of value only if the PCV of blood samples is adjusted to 40 p. cent.


[Bamifylline. Conditions of its interference in the estimation of urinary 17-oxosteroids. Method of estimation using Zimmermann's reaction (author's transl)]. Bamifylline in therapeutic dosage may markedly disturb the determination of urinary 17-oxosteroids by Zimmermann's reaction, although the conditions of extraction and formation of this chromogenic substance are not always optimal for the metabolites of bamifylline. It is easy to suspect this interference as the chromogenic substance is produced as soon as the reagents are introduced, contrary to 17-oxosteroids, and it presents a more bluish colour. It is possible to separate completely both types of metabolite by washing the chloroform extracts with acid solutions which form salts with bamifylline and thus extract it. From these acid solutions, bamifylline may be recovered and estimated Zimmermann's reaction which is, for this purpose, modified.


Monensin for the prevention of coccidiosis in calves. Young calves (Holstein-Friesian) were inoculated with Eimeria bovis on the 3rd day after the start of 31 days' feeding of a ration containing added monensin in 2 dose levels: 16.5 g or 33 g/metric ton of feed. Monensin-treated calves were free of clinical signs of coccidiosis, but inoculated control calves developed diarrhea and had excessive oocyst discharge on days 19 to 28 after they were inoculated. Weight gains and feed efficiency in monensin-treated calves were equal or superior to those factors in noninoculated control calves for the 31-day period.


Bone-remodeling rates of the Beagle: a comparison between different sites on the same rib. The standardized colony-raised male Beagle is being used more frequently for research purposes. The rib of this dog is an ideal bone on which to measure haversian bone-remodeling activity. To date there has been little indication as to whether there has existed any natural statistically significant differences in bone-remodeling rates along the length of the rib of this dog. To answer this question, standard samples were procured from the proximal, mid-shaft, and distal portions of the 5th, 7th, 9th, and 11th ribs after tetracycline labeling. It was found that there exist in the normal state statistically significant differences between the 3 portions on all the ribs examined, as refers to ratio of cortical to total bone area, number of osteoid seams, number of resorption spaces, activation frequency, and bone-formation rate. These differences are significant at the 0.001 level and may give rise to a wrong interpretation by the unwary investigator. The results of this investigation stress the importance of standardizing the biopsy site on the rib that is to be examined.


Enterotoxigenic Staphylococci of canine origin. Enterotoxigenic staphylococci were isolated from cecum and rectum from 26 (5.8%) of 451 dogs. Of the 30 enterotoxigenic staphylococci isolated, 14 (46.7%) belonged to biotype E, which has been considered to be of canine origin (Baird-Parker's classification modified by Hájek and Marsálek). They produced exclusively enterotoxin type C. This is the first evidence of enterotoxigenic staphylococci of canine origin.


Relationship of the patellar tendon reflex to the ventral branch of the fifth lumbar spinal nerve in the dog. The lumbosacral plexuses of dogs were exposed, using a ventral abdominal approach. In 4 dogs, the ventral branches (VB) of the 4th, 5th, 6th, or 7th lumbar spinal nerves were severed bilaterally. In 4 other dogs, the VB of combinations of 3 of these lumbar spinal nerves were severed so that the branch of only 1 nerve was kept intact. Among many neurologic deficits seen, the reflex of the patellar tendon was absent if the VB of the 5th lumbar spinal nerve was severed and was present if the branch was left intact. This finding was confirmed in another 12 dogs in which the VG of the 5th lumbar spinal nerve was severed on 1 side and the VB of the 4th and 6th lumbar spinal nerves were severed on the opposite side. In 4 additional dogs, the dorsal and ventral roots of the 5th lumbar spinal cord segment were isolated by dorsal laminectomy. Severing the dorsal root caused loss of the patellar tendon reflex, whereas severing the ventral root resulted in hyporeflexia. These findings would suggest that the major afferent impulse elicited by tapping the patellar tendon reaches the spinal cord by way of the dorsal root of the 5th lumbar spinal nerve.


Regulation by antibody of lectin-induced lymphocyte proliferation: antibody inhibition of mitogenesis and release of lectin from cell surfaces. Studies were conducted to determine the ways in which antibody regulates proliferation of lymphocytes stimulated by phytohemagglutinin (PHA) and concanavalin A (ConA). Equine lymphocytes were reacted with PHA or ConA for 1 to 10 hours, washed free of excess lectin, then cultured for 3 days and examined for proliferation and incorporation of [3H]thymidine. Both PHA and ConA induced lymphocytes to proliferate after short incubation periods. This response could be interrupted by the addition of antibody to the respective lectin. Total suppression of the proliferative response occurred if antibody was added within the first 2 hours after initial contact with PHA or ConA. Addition at times up to 48 hours produced either total or partial suppression. The removal of excess antibody 4 hours after addition to the culture did not reverse the suppression. Using radiolabeled ConA and PHA, it was observed that suppressive antibody inhibited the release of lectin from metabolically active lymphocytes and from surfaces where pinocytosis was not possible or was minimized. Antibody did not affect the rate of degradation of lectin by the cells. These results indicate that antibody attached to lectins, already bound to the lymphocyte surface, can terminate the lymphocyte response and retard the rate of release of lectin from the cell membrane.


Clinical pulmonary perfusion imaging in the dog. Scintigraphic pulmonary perfusion imaging in the dog has been described for the clinically normal animal. The usefulness of this technique in the patient with pulmonary dysfunction was assessed by review of 76 consecutive clinical cases completed in a 6-month period. This review indicated that 3 basic patterns of perfusion defects are commonly seen in the dog. These were associated with (1) diffuse parenchymal metastatic disease, (2) mediastinal metastatic disease, and (3) heartworm disease. The technique has proved reliable as an aid in the staging of neoplastic disease and of some potential value in heartworm disease and is now performed on a routine basis at this institution for purposes of clinical diagnosis.


Serum glutamic acid decarboxylase activity in normal dogs. Serum concentrations of glutamic acid decarboxylase, a nearly brain-specific enzyme, were determined in 290 samples from 29 normal Beagle dogs, using a modification of a fluorometric method. Mean glutamic acid decarboxylase activity was 214 micromoles/hr/L (units). Seemingly, 95% of clinically normal Beagles would have values between 93 and 335 units and 99% of the values would fall between 50 and 378 units.


Patent ductus arteriosus in the dog: a retrospective study of radiographic, epidemiologic, and clinical findings. Twenty-seven cases of patent ductus arteriosus (PDA) in the dog, which were confirmed by cardiac catheterization, surgical exploration, or at necropsy, were reviewed. A machinery murmur, electrocardiographic evidence of left ventricular enlargement, and radiographic evidence of cardiomegaly with an aortic and a pulmonary artery dilatation were consistent features. Surgical repair was successful in 65% of the dogs. The postoperative radiographic and electrocardiographic changes are described. A concomitant congenital defect was present in 2 dogs. The epidemiologic features of 532 dogs identified as having PDA and submitted to the National Cancer Institute's Veterinary Medical Data Program were reviewed. Miniature and Toy Poodles, Pomeranians, and Shetland Sheepdogs were identified as being at high risk for PDA. An excess of females over males was noticed.