Artificial Substitutes Research Articles

Protective Effects of Artificial Blood Substitute against Cerebral Ischemic Injury

Protective Effects of Artificial Blood Substitute against Cerebral Ischemic Injury

The Effects of an Artificial Meniscus Substitute in a Knee Joint With a Resected Anterior Cruciate Ligament

A Dacron meniscus prosthesis was substituted for the medial meniscus in an anterior cruciate ligament (ACL) resected rabbit knee. At three months, the joints were evaluated biomechanically, with gross and histologic inspection. In a paired comparison with the contralateral knee, differences between ACL resection with intact, incised, or resected medial menisci were evaluated. Knees with intact menisci and ligaments served as controls. Because of cartilage destruction, soft-tissue hypertrophy, and increased anterior laxity, joint stiffness was less than normal in all ACL-resected knees. Ingrowth and stable fixation, especially of the posterior horns of the prostheses and the incised menisci, were rare. Almost all normal menisci had ruptured in the same area. Anterior cruciate ligament resection led to severe osteoarthrosis in both compartments, regardless of initial meniscal treatment. Knees with prostheses had the same incidence and severity of osteoarthrosis as knees with meniscus resection. Anterior cruciate ligament resection alone induced excessive osteoarthrosis and synovitis and diminished the effects of different meniscal treatments three months earlier.

Polymerase chain reaction (PCR) mutagenesis enabling rapid non‐radioactive detection of common β‐thalassaemia mutations in Mediterraneans

The IVS-1-110 (G----A) and IVS-1-1 (G----A) mutations occur in approximately 33% and 9% respectively of beta-thalassaemia alleles in Mediterraneans (Kazazian & Boehm, 1988). They are generally detected in polymerase chain reaction (PCR)-amplified material by allele-specific oligonucleotide (ASO) hybridization patterns. In this study, artificial base substitutions in amplified material have been created to distinguish normal from mutant alleles on the basis of restriction enzyme digestion patterns. Invariant target sites provide an internal control for restriction enzyme activity. Mutagenesis was achieved by 3' base mismatches in primers selected to anneal immediately adjacent to target sites. Digestion of PCR products from normal and thalassaemic alleles with the restriction enzymes MboI (IVS-1-110) and HinfI (IVS-1-1) produced different fragments on electrophoresis. The above strategy was validated by allele-specific oligonucleotide probing. Identification of the three commonest mutations in this population (IVS-1-110, codon 39 and IVS-1-1), which account for approximately 69% of thalassaemic alleles (Kazazian & Boehm, 1988), was subsequently undertaken in seven chorion villus biopsies.

Experimental Vitreous Replacement With Perfluorotributylamine

Perfluorotributylamine, a liquid fluorochemical used in artificial blood substitution, was evaluated for potential application as a vitreous substitute having heavier density than saline. It was injected into the vitreous of 38 rabbit eyes after mechanical vitrectomy or gas compression of the vitreous with perfluoropropane. The eyes were observed for periods of up to five months. Clinically the liquid occupied the lower vitreous space but gradually dispersed into smaller fluorochemical droplets. In the upper vitreous clusters of cells appeared within three to four weeks which precipitated on the posterior lens surface and in the cortical vitreous. In eyes with experimental retinal detachment perfluorotributylamine had physical properties which provided mechanical retinal tamponade. Its interfacial tension prevented passage through iatrogenic retinal breaks. Histopathologic findings showed irregularly shaped defects in the outer segment disks as early as two days after vitreous replacement. These changes appeared to reverse if perfluorotributylamine was removed after two days. The cellular response in the vitreous consisted primarily of monocyte-derived macrophages capable of ingesting fluorochemical (foam cells).

Increased Infection Mortality and Decreased Neutrophil Migration Due to a Component of an Artificial Blood Substitute

Abstract We previously showed that an artificial blood substitute containing perfluorocarbons, Fluosol-DA, inhibited both neutrophil migration and adherence, due to its detergent component, Pluronic F-68. The purpose of the studies we report here was to determine if Fluosol or Pluronic might also reduce in vivo neutrophil migration and impair host resistance to bacterial infection. We studied in vivo PMN migration by injecting mice intraperitoneally (IP) with glycogen, followed by intravenous (IV) infusion of saline, Fluosol, or Pluronic. Peritoneal lavage after eight hours showed a significant decrease in the accumulation of PMN in lavage fluids of animals given either Fluosol or Pluronic (control--.19 +/- .03 X 10(6) PMN/mL, glycogen--1.35 +/- .14; glycogen/Fluosol--0.63 +/- .12; glycogen/Pluronic--0.69 +/- .07). We ascertained the effect of Fluosol and Pluronic on infection mortality by injecting mice IV with saline, Fluosol, or Pluronic, followed by a quantity of E coli (0.6 X 10(7] IP shown in preliminary studies to kill 20% to 50% of the mice in 24 hours. The 24-hour mortality was 14/45- saline, 24/32-Fluosol (chi 2 = 17.1; P less than .001) and 17/23 - Pluronic (chi = 11.2; P less than .001). Neither Fluosol nor Pluronic caused mortality without E coli. The increase in infection mortality occurred when Fluosol was given either two hours before, or simultaneously with E coli, but only with the simultaneous administration of bacteria and Pluronic. Pluronic did not alter reticuloendothelial system (RES) clearance function. These studies indicate that, in an animal model, Fluosol-DA, due to its detergent component Pluronic F-68, impaired neutrophil delivery to an inflammatory locus, and resulted in an increased rate of infection mortality. Since Pluronic did not result in RES blockade, but did impair the delivery of PMN to an inflammatory locus, our results suggest that the latter effect is responsible for the increase in infection mortality.

Paralysis of Phagocyte Migration Due to an Artificial Blood Substitute

We investigated the effect of a candidate artificial blood substitute, Fluosol-DA (FDA), on human neutrophil function in a serum-free medium. In a 50% (vol/vol) mixture with polymorphonuclear cells (PMN), FDA had no effect on PMN viability, phagocytosis, superoxide anion generation, degranulation, or bactericidal activity. In striking contrast, the random migration and chemotaxis of PMN to both f-Met-Leu-Phe (fMLP) and activated serum were inhibited by 98% +/- 2%, 95% +/- 2%, and 88% +/- 6%, respectively. Inhibition of chemotaxis by FDA required no preincubation, was dose-dependent (50% inhibition [ID50] with a 14% vol/vol mixture with FDA), and was fully reversible by washing PMN free of FDA after one hour but not after 18 hours of incubation (32% +/- 11% inhibition of chemotaxis). FDA itself was not chemotactic and did not impair either the chemotactic activity or binding of fMLP to PMN. FDA also inhibited PMN adhesion (ID50, 9 +/- 1 vol/vol%). The inhibitory component of FDA was found to be its detergent additive, Pluronic F-68, which inhibited random migration, chemotaxis, and adhesion with ID50s of 1.4, 2.4, and 2.9 mg/mL, respectively (equivalent to FDA concentrations of 5, 9, and 11 vol/vol%, respectively). All the other components of FDA were noninhibitory. Plasma samples from humans injected with 8 mL/kg FDA and plasma samples from rabbits injected with 16 mL/kg FDA or an equivalent concentration of Pluronic F-68, when mixed with autologous PMN, also severely inhibited PMN chemotaxis. We conclude that exposure of PMN to clinically relevant concentrations of FDA inhibits PMN migration, presumably due to inhibition of adhesion. The inhibitory effect is entirely due to the detergent, Pluronic F-68. Artificial blood substitutes containing Pluronic F-68 may compromise the ability of PMN to prevent or effectively control microbial infections.

膜トピックス

The recent situation of research and development on the following items is surveyed:(1) The characteristics (structure and functions) of biological membranes and synthetic membranes.(2) Materials, structures and shapes of the various kinds of the membrane separator.(3) Artificial organs-Partial substitution of some biological functions by synthetic polymers, for example, skin, eye, lung and kidney.(4) A role of synthetic membranes for use in the systems of blood component separation, blood purification and plasma exchange.(5) A co-operation of the artificial membrane with the biological substances - A cell culture on the surface of the synthetic membranes.

Organo-Fluorine Compounds as Artificial Blood Substitute

The rate of fluoro-carbon compounds as artificial substitute for blood has been discussed. Blood is a complicated body fluid. At first glance it seems impossible that such a complicated body fluid can be replaced by artificial synthesized fluids or any substitute for this can be synthesized. Fluoro-carbon compounds however have advanced research in this area because a number of fluoro-carbon have been found to be highly inert and have high solubility for O/sub 2/CO/sub 2/ and are able to transport O/sub 2/ CO/sub 2/ in vivo.

Demand-controlled liquid ventilation of the lungs.

Demand-controlled liquid ventilation of the lungs.

Filled Milk and Artificial Milk Substitutes

Filled Milk and Artificial Milk Substitutes

Effect of temperature on solubility of O2 in human plasma.

(See PDF) Page 58: in table 2, agr Blood values ascribed to Handbook of Raspiration should read 28 C 0.0285; 18 C No value.

Some aspects of simulating large scale atmospheric mixing

The classical picture of one-dimensional diffusion in a homogeneous fluid results in a symmetrical distribution of the conservative property around the peak concentration while the latter remains fixed in space. This paper examines the asymmetry and movement of the peak resulting from mixing in a non-homogeneous fluid. A one-dimensional model comprising 21 boxes permits the diffusive flux across the wall of each box equal to the coefficient of eddy diffusion times the air density multiplied by the gradient of (mixing ratio) concentration. The end boxes are half the volume of the others and there is no flux across the ends of the model. The divergence of this flux creates the change in concentration in each box. With constant diffusion coefficients and density, the peak (mixing ratio) concentration initially in the center of the model remains fixed and symmetry exists for all times as theory predicts. Firstly, placing the point source near either edge produces asymmetry due to reflection of the Gaussian curve, also in accord with theory. The peak concentration actually shifts with time, its movement depending on the magnitude of the eddy diffusion coefficient and proximity to the edge. Secondly, the peak concentration initially in the middle of the model moves upward for the case of a constant diffusion coefficient but with density decreasing as in the standard atmosphere. For example, for a coefficient of 10 4 cm 2 sec ?1 . The rate of rise increases with an increasing coefficient and vice versa. When the model contains a strong diffusion regime, or a troposphere, to about 9 km and a transition to smaller coefficients above 17 km, the stratosphere, then the rate of rise of the peak concentration increases (rising from 20 to 40 km in 24 rather than 30 months for a stratospheric coefficient of 10 4 cm 2 sec ?1 ). The removal of tracer material from below also increases the ascent rate of the peak concentration. Thirdly, models with constant density but variable coefficients of diffusion produce considerable asymmetry and some drift of the peak concentration with altitude. Finally, the one-dimensional model may be adapted to a spherical earth with constant horizontal air density. Material added at the equator diffuses symmetrically into both hemispheres as expected. But injections at other latitudes produce asymmetries such that, for example, the peak concentration shifts from 45° to the pole in 30 months if the coefficient of horizontal diffusion is 10 9 cm 2 sec ?1 An attempt will be made to explain the asymmetries and try to distinguish between possible real atmospheric effects and those due to the model simulation. The artificial substitution of a three dimensional world by a one dimensional model must be recognized. DOI: 10.1111/j.2153-3490.1966.tb00247.x

Some aspects of simulating large scale atmospheric mixing

The classical picture of one-dimensional diffusion in a homogeneous fluid results in a symmetrical distribution of the conservative property around the peak concentration while the latter remains fixed in space. This paper examines the asymmetry and movement of the peak resulting from mixing in a non-homogeneous fluid. A one-dimensional model comprising 21 boxes permits the diffusive flux across the wall of each box equal to the coefficient of eddy diffusion times the air density multiplied by the gradient of (mixing ratio) concentration. The end boxes are half the volume of the others and there is no flux across the ends of the model. The divergence of this flux creates the change in concentration in each box. With constant diffusion coefficients and density, the peak (mixing ratio) concentration initially in the center of the model remains fixed and symmetry exists for all times as theory predicts. Firstly, placing the point source near either edge produces asymmetry due to reflection of the Gaussian curve, also in accord with theory. The peak concentration actually shifts with time, its movement depending on the magnitude of the eddy diffusion coefficient and proximity to the edge. Secondly, the peak concentration initially in the middle of the model moves upward for the case of a constant diffusion coefficient but with density decreasing as in the standard atmosphere. For example, for a coefficient of 104 cm2 sec?1. The rate of rise increases with an increasing coefficient and vice versa. When the model contains a strong diffusion regime, or a troposphere, to about 9 km and a transition to smaller coefficients above 17 km, the stratosphere, then the rate of rise of the peak concentration increases (rising from 20 to 40 km in 24 rather than 30 months for a stratospheric coefficient of 104 cm2 sec?1). The removal of tracer material from below also increases the ascent rate of the peak concentration. Thirdly, models with constant density but variable coefficients of diffusion produce considerable asymmetry and some drift of the peak concentration with altitude. Finally, the one-dimensional model may be adapted to a spherical earth with constant horizontal air density. Material added at the equator diffuses symmetrically into both hemispheres as expected. But injections at other latitudes produce asymmetries such that, for example, the peak concentration shifts from 45° to the pole in 30 months if the coefficient of horizontal diffusion is 109 cm2 sec?1 An attempt will be made to explain the asymmetries and try to distinguish between possible real atmospheric effects and those due to the model simulation. The artificial substitution of a three dimensional world by a one dimensional model must be recognized.DOI: 10.1111/j.2153-3490.1966.tb00247.x

Experimental artificial heart implantation

1. 1. An artificial heart with external compression power and control of our own design has been described. 2. 2. Experience with twenty-one implantations in dogs is discussed with special reference to causes of failure. Loss of valve fixation and compressor breakdown accounted for most of the failures. 3. 3. At autopsy, clot was present in only one instance and this was secondary to left ventricular inflow stenosis due to faulty surgical technic. Virtual absence of thrombosis is attributed to valve design and use of polyurethane in making valves and ventricles. 4. 4. The features of this particular heart design that show merit along with indicated changes and improvements are discussed. 5. 5. The immediate value of a chronic preparation with artificial heart substitution is in its physiologic and pharmacologic applications.

Electrocardiograms of small mammals.

ArticleElectrocardiograms of Small MammalsElna A. LombardElna A. LombardFrom the Department of Physiology, University of Wisconsin Medical School, Madison, WisconsinPublished Online:30 Sep 1952https://doi.org/10.1152/ajplegacy.1952.171.1.189MoreSectionsPDF (689 KB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByThe Complex QT/RR Relationship in Mice3 May 2016 | Scientific Reports, Vol. 6, No. 1The Mammalian Electrocardiogram: Comparative Features27 September 2011Anatomy, Physiology, and BehaviorThe Mammalian Electrocardiogram: Comparative FeaturesEffects of Diaspirin Crosslinked Hemoglobin (DCLHb) on Microcirculation and Local Tissue P O 2 of Striated Skin Muscle Following Resuscitation from Hemorrhagic Shock11 July 2009 | Artificial Cells, Blood Substitutes, and Biotechnology, Vol. 34, No. 5The Sisyphean task of atrioventricular nodal scaling: Is the stone at the top of the mountain?Heart Rhythm, Vol. 2, No. 2From Mouse to WhaleCirculation, Vol. 110, No. 18ECG Monitoring and Analyses in Mice21 March 2011Correlation of repolarization of ventricular monophasic action potential with ECG in the murine heartStephan Danik, Candido Cabo, Christine Chiello, Sacha Kang, Andrew L. Wit, and James Coromilas1 July 2002 | American Journal of Physiology-Heart and Circulatory Physiology, Vol. 283, No. 1Rapid Ventricular Repolarization in Rodents: Electrocardiographic Manifestations, Molecular Mechanisms, and Clinical InsightsJournal of Electrocardiology, Vol. 33, No. 2ECG of the "Newborn" Mouse (Mus Domesticus) with Specific Reference to Comparative AV TransmissionJournal of Cardiovascular Electrophysiology, Vol. 10, No. 2Electrocardiography of the Asian small-clawed otter (Aonyx cinerea)Zoo Biology, Vol. 10, No. 3The usefulness of the resting electrocardiogram for characterizing acute Chagas' heart disease in the ratInternational Journal of Cardiology, Vol. 18, No. 3The resting electrocardiogram of t. cruzi-infected ratsRevista do Instituto de Medicina Tropical de São Paulo, Vol. 29, No. 4Electrocardiographic changes inT. cruzi-infected rats after the ajmaline testResearch in Experimental Medicine, Vol. 187, No. 3The electrocardiogram of European shrewsComparative Biochemistry and Physiology Part A: Physiology, Vol. 83, No. 4PhysiologyVentilatory Sniffing in the Albino RatPhysiological Zoology, Vol. 54, No. 2DeuterostomiaStudies on the Experimental Cardiac Involvement and Cell-Mediated Immunity in Germ-Free Mice Sensitized with Killed Group A Streptococci14 November 2013 | Microbiology and Immunology, Vol. 22, No. 7PhysiologyEquinatoxin, a lethal protein from Actinia equina—II. Pathophysiological actionToxicon, Vol. 12, No. 1The Changing Role Of Pathology In Modern Safety Evaluation26 September 2008 | CRC Critical Reviews in Toxicology, Vol. 1, No. 2Some Electrophysiological Methods for Studying the Action of Narcotic Agents in Animals, with special reference to Industrial Solvents: A ReviewOccupational and Environmental Medicine, Vol. 25, No. 2A SIMPLE METHOD FOR RECORDING THE ELECTROCARDIOGRAM AND HEART RATE FROM CONSCIOUS ANIMALS19 July 2012 | British Journal of Pharmacology and Chemotherapy, Vol. 32, No. 1Effect of Mescaline on Cardiopulmonary DynamicsJournal of Pharmaceutical Sciences, Vol. 56, No. 4COMPARATIVE ELECTROCARDIOGRAPHY*16 December 2006 | Annals of the New York Academy of Sciences, Vol. 127, No. 1THE CONFIGURATION OF THE T WAVE AND THE VENTRICULAR ACTION POTENTIAL IN DIFFERENT SPECIES OF MAMMALS*16 December 2006 | Annals of the New York Academy of Sciences, Vol. 127, No. 1Electrocardiogram in the Normal Rat and Its Alteration with Experimental Coronary OcclusionCirculation Research, Vol. 9, No. 2CHRONIC TOXICITY STUDIES ON FOOD COLOURS: Part IV. Observations on the Toxicity of Tartrazine, Amaranth and Sunset Yellow in Rats12 April 2011 | Journal of Pharmacy and Pharmacology, Vol. 10, No. 1 More from this issue > Volume 171Issue 1September 1952Pages 189-193 Copyright & PermissionsCopyright © 1952 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1952.171.1.189PubMed12985980History Received 5 May 1952 Published online 30 September 1952 Published in print 30 September 1952 Metrics