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Biomedical subjects

K M Moser

Publications and source records attributed to K M Moser.

At least 163 records · Page 9Linked to original sources
PubMed1980

Protease and antiprotease responses in lung and peripheral blood in experimental canine pneumococcal pneumonia.

We studied the effects of pulmonary infection with type III pneumococcus in dogs on the degree of granulocyte elastase-like esterase activity and on the degree of antiproteases in peripheral blood and lung lavage fluid. In 9 infected dogs the peripheral blood granulocyte esterase activity increased from a preinfection level of 361.3 +/- 51 units/10(8) leukocytes to 593.8 +/- 80 units/10(8) leukocytes (mean +/- SE) 24 h after pneumonia had been induced (p less than .02). Parallel changes were measured in granulocytes obtained from bronchial lavage fluid. The antitrypsin activity and esterase inhibitory activity of peripheral blood increased by 15% after infection was induced. The esterase inhibitory activity of lung lavage fluid increased from a preinfection level of 776 +/- 160 units/mg of lavage protein to 1,390 +/- 200 units/mg of lavage protein (p less than .05). These findings indicate that whereas both circulating and lung lavage granulocytes contain increased concentrations of proteolytic activity during infection, serum antiproteases and, to a larger extent, lung antiproteases, also are increased.

Animals↗
PubMed1980

Lamellar body depletion in dogs undergoing pulmonary artery occlusion.

We have investigated the relationship between pulmonary artery occlusion (PAO) and the surfactant system of the lung by studying the ultrastructural responses of type II alveolar pneumocytes to PAO of 4-12 h duration in 16 mongrel dogs. In six of these animals, the occluded lung was allowed to reperfuse for 6 h before killing and in four animals subjected to PAO of 4 h duration, the occluded lung was ventilated with 5% CO2 balance air. PAO by itself resulted in a dramatic 80% reduction in the volumetric density of lamellar bodies (LB) in the type II cells. This resulted predominantly from a decrese in volume of the individual LB. Although reperfusion was associated with an increase in LB volume density toward normal, 6 h of reperfusion was insufficient to re-establish normal type II cellular morphology. Ventilation of the occluded lung with 5% CO2 prevented LB depletion indicating that alveolar CO2 tension may affect the release and/or synthesis of LB in type II pneumocytes.

Animals↗
PubMed1980

Angioscopic visualization of pulmonary emboli.

A flexible, fiberoptic device, fitted with an inflatable distal balloon, has been used to directly visualize the great veins, right cardiac chambers, pulmonary arteries, and experimental emboli in vivo in the dog. Insertion and manipulation of the device have been well-tolerated. The angioscope has significant potential for investigative and clinical application.

Animals↗
PubMed1980

Results of a comprehensive rehabilitation program. Physiologic and functional effects on patients with chronic obstructive pulmonary disease.

Forty-two patients with chronic obstructive pulmonary disease participated in a comprehensive inpatient rehabilitation program. Criteria for a safe, maximum treadmill exercise regimen were established; all patients pursued this regimen for six weeks, without complications, even though 31 of 39 patients showed a decline in PaO2 with exercise. Postprogram O2 consumption, minute ventilation, heart rate, and respiratory rate were significantly reduced during exercise when compared with preprogram values. Sixteen of 29 patients improved in terms of dyspnea class; an additional 11 of these 29 improved with regard to activities of daily living. Most patients who improved physiologically also improved functionally. Patients able to tolerate higher levels of treadmill exercise initially had the greatest improvement in postcourse exercise performance. The data suggest that precourse functional and exercise classification is useful in selecting candidates who will receive the greatest functional benefits from participation in rehabilitative programs.

Activities of Daily Living↗
PubMed1980

Study of factors that may condition scintigraphic detection of venous thrombi and pulmonary emboli with indium-111-labeled platelets.

Incorporation of indium-111-labeled platelets (In-111-P) into venous thrombi and pulmonary emboli may permit rapid detection of these thromboemboli by gamma imaging. In a series of dogs in which femoral-vein thromboses and/or pulmonary embolism were induced experimentally by stasis and small amounts of thrombin, we addressed several questions pertinent to the sensitivity, specificity, and potential applicability of this approach. We found that when In-111-P were injected intravenously before thrombus induction or embolus release, femoral-thrombus images were consistently detectable within 15 min, whereas control femoral-vein images were unremarkable. Pulmonary emboli were also promptly imaged, and such In-111-P images agreed well with defects on Tc-99m MAA perfusion scans. When thrombi were aged in vivo for up to 10 hr after formation, they could still be imaged within 20-90 min after In-111-P injection. Administration of heparin, as an initial bolus followed by constant infusion, blocked platelet deposition on femoral-vein thrombi as assessed by both thrombus-to-blood ratios and failure to image. Injection of protamine at 6 hr, however, resulted in prompt thrombus imaging. These data indicate that this approach may well have applicability to the detection of thromboemboli in humans, since imaging remains possible in canine thrombi aged in vivo for 10 hr so long as heparin therapy has not been instituted. The dose of heparin required to inhibit imaging is not known. However, if these data prove comparable in humans, they suggest that imaging of thromboemboli could be achieved so promptly that only modest delay in the institution of heparin therapy would be required.

Animals↗
PubMed1979

Effects of isoproterenol on distribution of perfusion in embolized dog lungs.

In 19 mechanically venilated, anesthetized dogs, autologous venous thrombi were formed in the inferior vena cava and subsequently released. Serial perfusion lung scintigrams revealed the postembolic distribution of pulmonary blood flow before, during, and after the infusion of isoproterenol at 2.2 micrograms/min. Isoproterenol failed to restore perfusion to embolically occluded regions. When reperfusion occurred it was attributable to clot resolution. Gas exchange and hemodynamic measurements obtained in seven thromboembolized animals showed no scan evidence of reperfusion during the isoproterenol infusion. After embolization, cardiac output increased from 1.7 to 2.6 liter/min (p less than 0.05), and PvO2 from 38.0 to 45.3 mm Hg (p less than 0.05). Shunt fraction remained unchanged. The postembolic infusion of isoproterenol was associated with a further increase in cardiac output to 3.6 liter/min (p less than 0.01), an elevation in PvO2 to 50.7 mm Hg, along with a decrease in pulmonary vascular resistance from the postembolic mean of 448 to 246 dynes.sec.cm-5 (p less than 0.05). Perfusion defects following acute pulmonary thromboembolization are not altered by the infusion of the potent pulmonary vasodilator, isoproterenol. Infusion of this drug following thromboembolization may have potential therapeutic benefit by reducing pulmonary vascular resistance, increasing cardiac output, and elevating the mixed-venous oxygen tension.

Animals↗
PubMed1978

Functional residual capacity and body position in the dog.

Resting lung volumes in the supine position (FRCs) were determined by N2 washout method in 67 dogs under pentobarbital anesthesia and computed in ml/kg body weight (BW). In 21 other dogs, FRCs and the change in FRC from the supine to upright positions (deltaFRC) were determined; these lung volumes were expressed in ml/kg BW and in percentage of TLC40 (lung volume at 40 cmH2O positive-pressure inflation). It was found that a) FRCs averaged 38.6 plus or minus 8.2 and 42 plus or minus 5.9 ml/kg BW in the two groups of dogs; b) deltaFRC averaged 23 plus or minus 4 ml/kg BW resulted in large data dispersion, a large coefficient of variation (CV) and a poor correlation (r) of lung volume to BW; D) on the contrary, marked uniformity of FRCs and FRCu (upright FRC) was obtained by expressing the resting lung volumes in %TLC40, allowing an accurate prediction of FRC from the inspiratory capacity (IC). Relationship of FRCu to TLC was comparable to human data reported in the literature. FRCs (%TLC40) was smaller than values previously reported for awake human subjects, probably due to the FRCs reduction in our dogs by anesthesia.

Animals↗
PubMed1978

Changes in ventilation and perfusion in anesthetized dogs following lobar lavage with saline solution.

The therapeutic application of endobronchial lavage has been inhibited by concern regarding alterations in the exchange of gases, particularly hypoxemia, and by the technical complexity of the procedure. Using a cuffed fiberoptic bronchoscope with which lavage could be restricted to one lobe, we studied the sequence of alterations in the exchange of gases after lavage and the attendant disturbances in ventilation and perfusion in ten mongrel dogs following lobar lavage with 1,850 ml of physiologic saline solution. Sequential scintiphotographs of ventilation and perfusion and sequential measurements of arterial blood gas levels were obtained. Linkage of the computer to the scintillation camera allowed quantification of data on ventilation and perfusion from the lobar area of interest. Lavage induced a reduction in regional ventilation and perfusion in all dogs. The decline in ventilation preceded that in perfusion, and the computed ratio of ventilation over perfusion reached its lowest point during the first 30 minutes after lavage. The arterial oxygen pressure (PaO2) declined in all dogs from a mean baseline value of 87 mm Hg to a mean value of 76 mm Hg at 30 minutes after lavage and gradually returned to a mean of 85 mm Hg by six hours after lavage. The lowest value for PaO2 occurred after balloon occlusion prior to lavage. Calculations of shunt showed a minimal increment in the intrapulmonary shunt (Qs/Qt). In the normal dog, lobar lavage induces mild hypoxemia due to an imbalance of ventilation and perfusion that resolves within six hours.

Anesthesia, Local↗
PubMed1978

Biologic half-life and organ distribution of radiolabeled human PiM and PiZ alpha-1-antitrypsin in the dog.

Highly purified A-1-A.T., prepared from blood obtained from donors of known PiZZ and PiMM phenotype, was radiolabeled with 125I or 131I and injected intravenously into dogs. The radiolabeled proteins retained their prelabel electrophoretic and trypsin-inhibitory characteristics. The biologic t1/2 of both M and Z protein in the circulation were similar, averaging 71 hr for M protein and 80 hr for Z protein. The label was shown to remain tightly bound in vivo for 2 days after injection. The material was nonpyrogenic in rabbit and dog. No arteriovenous differences in radioactivity could be detected at 2 or 20 min after injection. However, surface scanning disclosed substantial pulmonary deposition of radioactivity for the first 9 hr after injection. At 48 hr, intense radioactivity was present in the spleen, but not in the liver. These studies indicate the feasibility of similar studies in man, including noninvasive assessment of body distribution of M and Z protein by surface scanning techniques.

Animals↗
PubMed1977

Clinically suspected deep venous thrombosis of the lower extremities. A comparison of venography, impedance plethysmography, and radiolabeled fibrinogen.

To define the utility of new diagnostic approaches in patients with clinically suspected deep venous thrombosis of the lower extremities, 42 legs of 33 patients were studied by fibrinogen labeled with radioactivie iodine (125I) impedance plethysmography (IPG), and contrast venography. The clinical diagnosis was confirmed in approximately two thirds of the legs and patients. In venogram-positive legs, fibrinogen 125I was positive in 70%, IPG in 61%, and one of the two in 78%. In venogram-negative legs, fibrinogen 125I was positive in four (21%) and IPG was negative in all. It was found that the size, age, and location of the thrombus, collateral vein development, heparin sodium therapy, and technical-interpretive choices can influence both IPG and fibrinogen 125I results. The data demonstrate that the fibrinogen 125I and IPG procedures can assist physicians in the diagnosis of clinically suspected deep venous thrombosis of the lower extremities.

False Negative Reactions↗
PubMed1977

Venous thrombosis in acute spinal cord paralysis.

Radiolabeled fibrinogen, impedance phlebography and venogram surveillance were carried out in ten consecutive acute spinal cord paralysis patients. Nine patients had evidence of deep venous thrombosis by radiolabeled fibrinogen technique. Venogram confirmed the presence of venous thrombosis in seven. Impedance phlebography was positive in only four. Eight patients developed a positive radiolabeled fibrinogen test after a surgical procedure. One patient with extensive venous thrombosis had multiple pulmonary emboli.

Adolescent↗
PubMed1977

Light sources as a means of reproducing patient positioning.

A simple method to insure the reproducibility of patient positioning is described. The system uses an adjustable frame fastened to the camera head and two light sources. The light sources project two circles of light on the patient. These reference points are marked on the patient's skin with a felt pen. If the patient moves or requires a follow-up study, these two reference points can be used to reposition the patient exactly. Comparison of the light-sources method with the persistence-scope method showed a significant improvement in accuracy with the former.

Light↗
PubMed1977

Relationship of leukocyte elastase concentration to severity of emphysema in homozygous alpha1-antitrypsin-deficient persons.

In 9 alpha1-antitrypsin-deficient (PiZZ) persons 40 to 53 years of age, the relationships between the concentration of elastolytic protease of polymorphonuclear leukocyte granules and cigarette smoking, and the degree of abnormality in detailed pulmonary function tests were explored. Regardless of the statistical analytic approach used, elastase concentration was related more frequently and significantly than smoking history to the degree of abnormality observed in tests of pulmonary function. The data suggest that the severity of pulmonary dysfunction in PiZZ persons may be determined by variables other than age and cigarette smoking, including the concentration of elastolytic protease in leukocyte lysosomes.

Adult↗
PubMed1977

Cervical accessory respiratory muscle function in a patient with a high cervical cord lesion.

The function of the accessory respiratory muscles (ARM) of the neck were studied in a quadriplegic patient suffering from a C2-3 lesion of the cervical spinal cord. Subtotal expiratory paralysis resulted in an essentially complete loss of expiratory reserve volume such that residual volume and functiona residual capacity were equal (RV=FRC). Tidal volume and vital capacity were severely reduced. Being extrinsic to the chest, the ARM of the neck functioned independently of changes in thoracic gas volume; however, their performance appeared posture-dependent, and was less efficient in the sitting position. Despite the fact that the ARM preferentially expanded the upper part of the ribcage, significant V/Q mismatch did not seem to occur. Voluntary use of glossopharynegeal breathing (GPB) greatly enhanced the patient's ventilatory capability. Flow volume data during GPB documented the efficiency of the glossopharyngeal muscles, which function as a positive pressure pump to force air into the lungs.

Adult↗