Effects of nicotine on salivary amylase secretion from rabbit parotid gland.

1. The effects of nicotine on amylase secretion induced by auriculo-temporal nerve stimulation were studied.2. Nicotine caused a transient increase in secretion as well as flow rate of amylase.3. No difference in nicotine action was found between acute sympathetic decentralization of the gland and acute denervation.4. The increase in amylase secretion due to nicotine was not inhibited by phenoxybenzamine, bretylium and chronic denervation, but was prevented by hexamethonium, propranolol and adrenalectomy.5. The increase in flow rate due to nicotine was not inhibited by propranolol, chronic denervation and adrenalectomy, but was prevented by hexamethonium, phenoxybenzamine and bretylium.6. These results show that the action of nicotine in increasing amylase secretion is neither a direct action on the ganglion nor on the nerve terminal of the cervical sympathetic nerve, but is an indirect action of catecholamines released from the adrenal medulla on the post-junctional receptors.7. The study also suggests that the initial acceleration of salivary flow due to nicotine is characterized by a mechanism different from that of amylase secretion.

The effects of pressure and flow on hemolysis caused by Bio-Medicus centrifugal pumps and roller pumps. Guidelines for choosing a blood pump.

Two Bio-Medicus BP-50 centrifugal pumps and two roller pumps were tested simultaneously with porcine blood at 21 degrees +/- 1 degree C in four in vitro circuits to determine the effect of four combinations of flow and pressure conditions on blood damage. Flows of 300 ml/min (1/4-inch inner-diameter tubing in the roller pump) and 1775 ml/min (1/2-inch inner-diameter tubing in the roller pump) and pressure differences across the pump (delta P = outlet pressure--inlet pressure) of 215 mm Hg (n = 6) and 345 mm Hg (n = 5) were examined. The index of hemolysis (milligrams plasma hemoglobin per 100 L blood pumped) for the BP-50 pump was higher at a flow of 300 ml/min than at a flow of 1775 ml/min (p < 0.0002). At 300 ml/min, the index of hemolysis for the BP-50 pump tended to be higher at 345 mm Hg than at 215 mm Hg (mean +/- standard error of the mean, 135 +/- 22 versus 88 +/- 9, p = 0.059). At 1775 ml/min, there was no difference in the index of hemolysis for the BP-50 pump between 215 and 345 mm Hg (37 +/- 7 versus 29 +/- 5, p = 0.32). With the roller pump, the index of hemolysis was higher at a flow of 300 ml/min than at a flow of 1775 ml/min (p < 0.036), but there was no difference in the indexes of hemolysis between 215 and 345 mm Hg at 300 ml/min (60 +/- 9 versus 61 +/- 11, p = 0.93) or at 1775 ml/min (40 +/- 6 versus 36 +/- 6, p = 0.61). Comparison between the two types of pumps showed that the index of hemolysis was significantly higher for the BP-50 than for the roller pump at a flow of 300 ml/min and a delta P of 215 mm Hg (88 +/- 9 versus 60 +/- 9, p = 0.009), as well as at a flow of 300 ml/min and a delta P of 345 mm Hg (135 +/- 22 versus 61 +/- 11, p = 0.001). At a flow of 1775 ml/min, there was no difference in the index of hemolysis between the two pumps at either pressure condition.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional changes in platelets during extracorporeal circulation.

An in vitro trauma test was conducted to determine the effects of extracorporeal circulation on platelet count and function. Fresh human blood was circulated in two identical in vitro circuits for six hours at a rate of 500 ml per minute (500 recirculations). One circuit included a G.E.--Peirce membrane lung and the other was a control. Platelet aggregation induced by adenosine diphosphate (ADP), epinephrine, or collagen was studied before and after six hours of perfusion. No important drop in platelet count occurred in the control circuit (Control-C) following bypass, but there was a 20% drop for the lung circuit (Lung-C). Platelet aggregation was reduced by about 30% for the control circuit and 65% for the lung circuit. The large decrease in platelet function accompanied by only a moderate decrease in platelet count is discussed in terms of loss of the youngest and most active platelets, platelet inhibition due to ADP released by red blood cell lysis, and platelet trauma.

Thermoregulation and hypothalamic histamine turnover modulated by interleukin-1 beta in rats.

To clarify the involvement of hypothalamic histamine in thermogenic response provoked by high ambient temperature, or interleukin-1 beta (IL-1 beta), changes in rectal temperature and histamine turnover were investigated. Rectal temperature was maintained normally after exposure to high ambient temperature, but elevated by IL-1 beta. In spite of these different responses of body temperature, hypothalamic histamine turnover was increased in each treatment. The results suggest that hypothalamic histaminergic neurons are activated not only peripherally by high ambient temperature, but also centrally by IL-1 beta as endogenous pyrogen.

Longitudinal study on selenium content in human milk particularly during early lactation compared to that in infant formulas and cow's milk in Japan.

239 samples of human breast milk were collected from 36 healthy Japanese women. Selenium content of the samples was determined mainly by highly sensitive fluorometric analysis with 2,3-diaminonaphthalene. The highest selenium content, 247 micrograms/kg, was found on the first day postpartum. The arithmetic mean of selenium content was higher in colostrum (< 4 days) 47 micrograms/kg (SD 42, n = 116) than in transitional milk 24 micrograms/kg (SD 13, n = 87) or in mature milk (> 10 days) 10 micrograms/kg (SD 4, n = 36). Selenium content was also determined for six brands of commercial infant formula powder (32-58 micrograms/kg) based on cow's milk, seventeen brands of cow's milk (10-25 micrograms/kg) and eight brands of powered cream for cofee (9-162 micrograms/kg). The average selenium content was significant lower in the liquid formula prepared for infant lactation, 6.0 micrograms/L, than in the human colostrum and transitional milk. The dietary selenium intake of newborns fed on colostrum is estimated to be in the range of 2-12 micrograms per day.

Longitudinal study of the dietary selenium intake of exclusively breast-fed infants during early lactation in Korea and Japan.

213 samples of human breast milk were collected from 51 healthy Korean women. Selenium content of the samples was determined by atomic absorption spectrometry with hydride generation. The selenium content of Korean milk decreased with increase of days after birth: The arithmetic mean of selenium content was higher in colostrum (< 4 days) 34 micrograms/kg (SD +/- 11, n = 44) than in transitional milk 21 micrograms/kg (SD +/- 8, n = 78) or in mature milk (> 10 days) 13 micrograms/kg (SD +/- 6, n = 91). The daily dietary selenium intake of 0-1 month aged Korean infants fed on breast milk is estimated to be around 10 micrograms per day (3 micrograms/kg body weight) regardless of days postpartum, resulting from the calculation of our selenium data and daily milk intake during early lactation. The same result on selenium intake for Japanese newborns, as well as Korean infants, is also estimated to be around 10 micrograms per day (3 micrograms/kg body weight) regardless of days postpartum.

Quantitation of taurine and selenium levels in human milk and estimated intake of taurine by breast-fed infants during the early periods of lactation.

With these results we report the following: Taurine levels in human milk decreased slightly during the early lactation period. The concentration of taurine (406 +/- 174 nmol/ml) in colostrum was significantly higher than that (335 +/- 115 nmol/ml) in mature milk. Selenium content of human milk also decreased slightly during the early lactation period. The content of selenium (28.6 +/- 19.6 ng/ml) in colostrum was significantly higher than that (1 5.1 +/- 5.9 ng/ml) in mature milk. A correlation was not found between the taurine and selenium content of human milk. The intake of taurine and selenium by breast-fed infants progressively increased with days postpartum. These results were due to the significant increase in milk intake by infants. It is suggested that the taurine and selenium levels in colostrum are more concentrated than those in mature milk. However, the absolute intake of taurine and selenium by infants are higher in mature milk.

Experimental evaluation and clinical application of intraoperative counterpulsation without balloon pumping.

Cardiac assistance in the form of counterpulsation (CP), created by intraaortic balloon pumping (IABP), has recently been utilized to wean patients from cardiopulmonary bypass (CPB) after conventional modalities have failed. The use of IABP, however, is often delayed because it is not part of the standard CPB setup and requires an additional cutdown, an arterial graft, and the retrograde insertion of a foreign body into the arterial tree. To eliminate the disadvantages of IABP, an alternate technique for CP has been developed. A pneumatially actuated external blood reservoir connected via a "Y" connector to the standard arterial line of the CPB circuit can provide pulsatile flow, and when synchronized with the EKG, CP with or without CPB. Experimental evaluation with dogs comparing this technique with IABP has shown that the former can create comparable CP pressure curves to the latter. The technique was applied to 11 patients undergoing either aorto-coronary bypass surgery and/or valvular surgery. Two of the 11 patients could come off CPB only with the assistance of CP. Coronary bypass graft flow, when measured, increased by 25% due to CP in two out of seven patients. The arterial CP technique has proven to be easily adapted to clinical settings and provides immediate and effective CP when required.

A dynamic method for setting roller pumps nonocclusively reduces hemolysis and predicts retrograde flow.

In general, roller pumps are set almost occlusively despite evidence that nonocclusive settings cause less hemolysis. Almost-occlusive settings are used because of the concern that forward flow would not be accurately known if retrograde flow were allowed to occur through a nonocclusive gap. This article presents a dynamic method for setting roller pumps nonocclusively that overcomes the many difficulties of the "drop method" for setting occlusion. Studies were conducted to determine the effect of nonocclusive settings on pump flow and hemolysis generated; the results suggest that roller pumps can and should be set more nonocclusively than is the currently accepted standard to reduce pump related hemolysis without greatly affecting pump performance. The dynamic method allows retrograde flow to be easily predicted and corrected with an increase in pump speed.

Bloodless testing for microporous membrane oxygenator failure: a preliminary study.

The use of a bloodless solution and high pressure to accelerate microporous membrane oxygenator (MMO) failure was investigated. It was hypothesized that albumin acts as a wetting agent, contributing to plasma leakage through the membrane, and that high MMO outlet pressure accelerates the process. Three MMO, B-Bentley BCM-40 (n = 7), M-Medtronic Maxima (n = 4), and S-Sarns 16310 (n = 7) were tested at 37 +/- 2 degrees C using three identical closed recirculating circuits and four conditions: 1) Lactated Ringer solution (LR) with MMO outlet pressure (Pmo) 750 mmHg; 2) LR + albumin (4 g/100 ml), Pmo 150 mmHg; 3) LR + albumin, Pmo 300 mmHg; and 4) LR + albumin, Pmo 750 mmHg. "Blood" flow and gas flow were maintained at 2 l/min. Failure was indicated when Na+ was detected in the effluent of the MMO exhaust gas. There were no failures without albumin in the solution. B and M showed no signs of failure under any of the test conditions at 78 hours. S failed at (mean +/- SEM) 4.9 +/- 1.0, 12.1 +/- 0.2, and 19 hours for conditions 4, 3, and 2 respectively. Preceding failure, inlet gas pressure increased more than eightfold (27 +/- 1 to 224 +/- 34 mmH2O). These preliminary results are similar to previous findings with blood and suggest that high MMO outlet pressure and the presence of albumin may promote plasma breakthrough for S. The combination may provide a basis for an accelerated bloodless test for MMO compatibility with long-term respiratory support.

An improved bladder for pump control during ECMO procedures.

A new inline reservoir called the Better-Bladder, now FDA-cleared for long term use, overcomes some disadvantages of the silicone bladder and bladder box used in extracorporeal membrane oxygenation circuits. The Better-Bladder provides compliance in the venous line and allows for noninvasive pressure measurements. Both features are useful for controlling pump speed as a function of venous line pressure. Bench tests showed that the Better-Bladder measures pressure noninvasively within +/- 4% of invasive (i.e., liquid contacting) pressure measurements in a range from -200 to +500 mmHg and at temperatures from 10 degrees C to 37 degrees C. After 60 days, the error in noninvasive pressure measurement with the Better-Bladder was less than +/- 3%. The Better-Bladder withstood pressurization to 1700 mmHg for ten days without leaking or failing in other ways. The advantages of the Better Bladder, along with its accuracy and durability, suggest its use for short and long term pumping applications.

Errors in flow and pressure related to the arterial filter purge line.

The purge line is a necessary component on arterial filters, although its presence may affect the amount of flow reaching the patient as well as the pump outlet pressure in the extracorporeal circuit. In-vitro and clinical studies conducted to investigate these effects with a commonly used purge line showed that at flows less than 1.5 L/min, rates for pediatric or infant patients, the purge line diverts as much as 40% of the intended pump flow away from the patient. A small diameter resistance tube connected in series with the purge line reduced purge flow such that over 80% of the pump flow reached the patient. Pressure monitored at the arterial filter port with the purge line open could be as much as 45 mmHg lower than the pressure measured with the purge line closed to the filter. Studies should be done to determine if the arterial filter purge line compromises flow to the patient, and if an additional resistance to the purge line is appropriate to reduce the flow through it.

New roller pump disposable provides safety and simplifies occlusion setting.

A new disposable insert for the arterial roller pump, the Better-Header, provides safety and functionality beyond what standard tubing provides. It automatically limits pump outlet pressure to a level determined by the user and provides a self-contained, simple means to set pump occlusion. The Better-Header consists of a Starling-like pressure relief valve connected across standard header tubing. As long as arterial line pressure at the pump outlet remains below a set limit, the valve is closed. If line pressure approaches the pressure limit, the valve opens, preventing overpressurization by shunting blood from pump outlet to inlet. The Better-Header can also be used to set occlusion by the "dynamic method" to obtain nonocclusive settings. The Better-Header was evaluated in the lab for its pressure-flow characteristics. Even when the arterial line was completely clamped at a pump flow of 7 L/min, line pressure was limited to a safe level and all circuit connections were preserved. The Better-Header has been used successfully at North Shore University Hospital in over 500 clinical cases covering a wide range of patients and procedures. In several instances, the user was alerted to high pressure situations by fluid flow through the valve and by an audible alarm, allowing rapid correction of the source of pressure. Compared to the standard setup, the Better-Header maintains outlet pressure within safe, user-settable limits, and permits consistent, nonocclusive settings with predictable retrograde flow.

[Successful treatment of a pretreated elderly case of small-cell lung carcinoma with continuous five-day intravenous infusion of cisplatin plus etoposide].

A 78-year-old man was admitted to our hospital with dyspnea in June 1988, and diagnosed as having small-cell lung carcinoma by cytological findings of pleural effusion. He was treated three times with CAV (cyclophosphamide, doxorubicin, vincristine) therapy and a partial response was achieved. In March 1989, he was again admitted complaining of right dull hypochondralgia accompanied by enlargement of primary tumor in the right lower lobe of the lung and metastases to mediastinal and intraabdominal lymph nodes. Because it was an aged and recurrent case, he was treated with continuous five-day infusion of etoposide, 30 mg/m2/day and CDDP, 18.5 mg/m2/day. After the second course, subjective symptoms clearly disappeared and swelling of mediastinal and intraabdominal lymph nodes was markedly reduced on computed tomography. No severe side effects except for moderate myelosuppression, alopecia and nausea were observed. This regimen appears useful in the treatment of small-cell lung carcinoma in elderly patients.

Suppressive effect of ascorbic acid on the mutagenesis induced by the bystander effect through mitochondrial function.

Here, we focused on suppressive effect of ascorbic acid (AsA) on changes in mitochondrial function and mutagenesis by the radiation- induced bystander effect (RIBE). In mammalian cell lines, medium transfer assay was performed and conditioned medium including secreted factors after X-irradiation were examined to detect the RIBE. We found that the membrane potential and increased levels of superoxide radical (O2(-)) in mitochondria were modulated in cells treated with conditioned medium from irradiated cells. The result of the present study also demonstrated that increases in reactive oxygen species (ROS) levels led to the induction of gene mutations. Interestingly, the modulations in mitochondria, in addition to mutation inductions by RIBE, were completely suppressed by treatment with AsA in cells treated with conditioned medium. These results suggest that mutagenesis, which may have resulted from secreted factors involving the RIBE, may be induced by ROS that are localized in mitochondria and may be relieved by AsA.

Comprehensive diagnosis of growth rates of the ablative Rayleigh-Taylor instability.

The growth rate of the ablative Rayleigh-Taylor instability is approximated by gamma = square root[kg/(1 + kL)] - beta km/rho(a), where k is the perturbation wave number, g the gravity, L the density scale length, m the mass ablation rate, and rho(a) the peak target density. The coefficient beta was evaluated for the first time by measuring all quantities of this formula except for L, which was taken from the simulation. Although the experimental value of beta = 1.2+/-0.7 at short perturbation wavelengths is in reasonably good agreement with the theoretical prediction of beta = 1.7, it is found to be larger than the prediction at long wavelengths.

Neutron activation analysis of selenium and 17 elements in sediment.

Instrumental neutron activation analysis was performed to determine Na, Mg, Al, Cl, Sc, V, Cr, Mn, Fe, Co, Ni, Rb, Sb, Cs, Ba, Ce and Eu in the Pacific core sediment. Selenium was also determined by neutron activation analysis, by applying a solvent extraction method with 2,3-diaminonaphthalene (DAN) as a post-irradiation procedure, after the wet-ashing of the sediment. Homogeneity of trace constituents in the sediment and neutron flux corrections for accurate determination were also investigated.

Fluorometry of nanogram amounts of selenium in biological samples.

For fluorometry of selenium in human blood, hair, and liver and in leaves, we wet-ashed the samples with conventional nitric and perchloric acids, and then extracted piazselenol (complex of Se and 2,3-diaminonaphthalene) in cyclohexane. Selenium was back-extracted from the cyclohexane into nitric acid to remove the fluorometric interferences of trace amounts of organic compounds. This fluorometric method is rapid and suitable for routine analysis. We applied the method to human hair samples and compared it with the data for non-destructive neutron activation analysis of the hair.

Current priming solutions for cardiopulmonary bypass contain a potent coronary vasodilator.

We studied the effects of acetate (Ac), the buffer in crystalloids used during cardiopulmonary bypass (CPB) (e.g. Normosol-R and Plasma-Lyte, Ac = 27mEq/l), on coronary resistance (R) for the empty beating heart, and on vascular resistance (SVR) of 19 dogs on CPB. Control R with Ac = O (R c) was obtained by adjusting flow to give a pressure of 90 +/- 10mmHg (R = 532 +/- 32 dynes sec/cm 5g, other Rs are given as a percentage of their respective R c). Continuous addition of Ac = 1.6 or 7.1mEq/L of blood resulted in a rapid decrease in R to 34 +/- 3 and 17 +/- 2% of R c, followed by a recovery to higher steady values of 53 +/- 3 and 27 +/- 2% respectively (p less than 0.008). A bolus administration of 2mEq and 6mEq into the coronary circuit resulted in R dropping to 30 +/- 5 and 17 +/- 6% respectively. Rs obtained with Ac were compared to the Rs obtained for control 20sec reactive hyperaemia (35 +/- 1%), after 30 minutes global ischaemia (14 +/- 1%), and with the addition of bicarbonate (98 +/- 2%). Ac did not change heart rate, but caused an increase in O 2 consumption from 3.4 +/- 0.4 to 4.8 +/- 0.7 ml/min/100g, (p less than 0.038). Systemically, a bolus of 6mEq of Ac caused an immediate drop in SVR to 45 +/- 5% of control. The property of Ac as a potent coronary and vascular dilator may need to be considered when Ac is used during cardiac surgery. Statistical comparisons were made with the paired t-test.

2-deoxy-D-glucose suppresses food intake through activation of hypothalamic histamine in rats.

The aim of this experiment was to demonstrate whether brain histamine contributes to delayed suppression of food intake after administration of 2-deoxy-D-glucose (2-DG). Food intake decreased significantly for 48 h after infusion of 2-DG into the rat third cerebroventricle. This delayed decrease in food intake was abolished by depletion of neuronal histamine by intraperitoneal pretreatment with alpha-fluoromethylhistidine (160 mumol/rat), a suicide inhibitor of a histamine-synthesizing enzyme. Intracerebroventricular infusion of 24 mumol 2-DG accelerated turnover rate of hypothalamic histamine. These results indicate that the delayed feeding suppression by 2-DG is modulated through histaminergic neurons in the hypothalamus. This histaminergic response may be related, at least in part, to homeostatic control of energy metabolism in the brain.