Influence of the polymerization step alone on oxygen affinity and cooperativity during production of hyperpolymers from native hemoglobins with crosslinkers.

The aim of this study was to find out how the polymerization per se changes oxygen affinity (P50) and cooperativity (n50) of various soluble huge hyperpolymers prepared from native hemoglobins by crosslinking. Increase of cooperativity would be expected considering natural hemoglobin networks. Those hyperpolymers with molecular weights of some 10(6) g/mol are candidates for artificial oxygen-carrying blood additives rather than volume substitutes. Human and bovine hemoglobin reacted with several crosslinkers (2,5-diisothiocyanatobenzenesulfonate (DIBS); 4,4'-diisothiocyanatostilbene-2, 2'-disulfonate (DIDS); 1,3-butadiene diepoxide (BUDE); glutaraldehyde (GDA)) in concentrated (case 1) and …

Eine neue Möglichkeit zur Untersuchung der Reaktionen und Eigenschaften der Bronchialmuskulatur am Menschen. Die Wirkung von Histamin auf den Bronchialtonus

Mit Hilfe einer neuen Mesmethode ist es moglich, das anatomische Totraumvolumen (VD) direkt am Menschen, Atemzug fur Atemzug zu messen (Barnikol u. Diether, 1975, 1977) und damit auch seine kurzzeitigen Anderungen zu erfassen. Prinzipiell stutzt man sich bei der Methode auf das Plateau der Totluft in der Exspirationskurve und nicht wie die Fowlersche Methode auf das alveolare Plateau. Bei pulmonalen Storungen ist das alveo-lare Plateau so stark verandert, das keine exakte Totraumbestimmung mit der Fowler-schen Methode mehr durchgeffihrt werden kann. Der grose Vorteil der Methode des Totluft-Plateaus liegt darin, das sie pulmonalen Storungen gegenuber nahezu unanfallig ist; denn es gibt prak…

Measurement of phase I volume breath by breath in spontaneously breathing guinea pigs.

A new method to determine phase I volume in tracheotomized spontaneously breathing guinea pigs is presented. Measurements were performed in three animals weighing 567-896 g. In simultaneous tracings of tidal volume (VT) and expiratory profiles of endogenous gases (PO2 or PCO2), the phase I volume of each breath was determined graphically as the volume expired up to the end of phase I of the expirogram. The mean phase I volume of different animals ranged from 0.29 to 0.43 ml with an arithmetic dispersion between 0.014 and 0.021 ml. Spontaneous sighs sometimes with doubling of the VT caused a significant rise of phase I volume up to 50% of the normal values. The linear regression curve was c…

Ein neuartiges Verfahren der Sauerstoffdetektion für Medizin, Biologie, Umweltforschung und Biotechnik auf Basis der Lumineszenzlöschung - An Innovative Procedure for the Detection of Oxygen Based on Luminescence Quenching, for Use in Medicine, Biology, Environmental Research and Biotechnology

For most (aerobic) animal organisms, oxygen is a mandatory and global substrate. The accurate measurement of oxygen is therefore of importance in the fields of medicine, biology, environmental research and biotechnology. The fact that oxygen is not readily soluble in aqueous media makes its detection more difficult. In contrast to the technique of polarography, the use of luminescence quenching by paramagnetic oxygen, does not consume the oxygen. Another problem of oxygen detection in connection with respiration is the need for very short response times. A third problem, which is associated with luminescence itself, is the fading of the dyes, which results in long-term signal instability. T…

Eine neue Methode zur Messung des anatomischen Totraumes mit Hilfe des Totluft-Plateaus

Im Exspirationsrohr eines Atemventils, welches sich nahe am Mund des Probanden befindet werden gleichzeitig O2-Partialdruck mit einer O2-Elektrode und exspiriertes Volumen mit einem Pneumotachographen gemessen. Die PO2-Anzeige hat eine 90%-Einstellzeit von 40 ms. Wahrend der Totluft-Bolus die O2-Elektrode passiert, wird das sogenannte Totluft-Plateau gemessen. Das bis zum Ende des (korrigierten) Totluft-Plateaus exspirierte Volumen entspricht dem Totraumvolumen. Das Totluft-Plateau wird durch Stromungs- und Diffusionsverbreiterung im Respirationstrakt verkurzt. Die Verbreiterung wird im Exspirationsrohr simuliert, sowie mit einer zweiten O2-Elektrode gemessen und als Korrektur berucksichtig…

Experimente zur Entwicklung eines implantierbaren und dauernd funktionsfähigen Glukose-Sensors auf Basis der Polarimetrie - Experiments Aimed at Enabling the Development of an Implantable Glucose Sensor Based on Polarimetry

In vitro and in vivo experiments devised with the aim of developing a permanently implantable glucose sensor based on polarimetry are described. It was found that in ultrafiltrated human blood plasma the overall optical rotation was 94% specific for glucose, and that polarisation photometry yielded a sufficiently sensitive signal for in vivo glucose detection. The three types of capillary membrane intended for implantation that we tested, revealed an in vitro response time to glucose concentration of 10 minutes; when implanted, they maintain this over a period of weeks, during which time the same glucose concentrations can be measured daily in ultrafiltrated capillary fluid as in the blood …

The Measurement of the CO2 Hb Binding Curve of Human Hemoglobin by 13C-NMR Spectrometry

It is well known that under physiological conditions CO2 binds to the four terminal amino groups of hemoglobin (Hb) (Kilmartin and Rossi-Bernardi, 1971). The carbamino compounds which are formed by this reaction are involved in the Haldane effect.

Ein Mikro-Atemstromventil für spontan atmende narkotisierte Kleintiere - A Respiratory Micro-Valve for Spontaneously Breathing Anaesthetized Small Animals

For the accurate functional analysis of the gas exchange in the lungs or evaluation of artificial oxygen carriers in spontaneously breathing anaesthetized small animals, we developed a new respiratory micro-valve. The body of the valve is made of aluminium, and the flaps are made of silicone rubber. The maximum flow rate in a rat measured with a pneumotachograph and the micro-valve was an average of 19.9 ml/s during inspiration, and 17.8 ml/s during expiration. The pressure measured in the tracheal tube was -0.85 during inspiration, and +0.39 cm H2O during expiration; the end-expiratory pressure in the tube was zero. In two experiments with anaesthetised rats lasting 4-5 hours, ventilation,…

Über die klinische Anwendbarkeit der Methode des Totluftplateaus zur Messung des anatomischen Totraumes

Die neue Methode des sogenannten Totluftplateaus lies von der Konzeption her erwarten, das sie auch bei Patienten mit gestorter Lungenfunktion richtige Werte fur das anatomische Totraumvolumen liefert. Es wird daher die neue Methode intraindividuell mit der bekannten Methode nach Bohr und der Totraumbestimmung mit Hilfe der graphischen Auswertung nach Fowler (O2 als Mesgas) an 6 mannlichen Patienten mit unterschiedlichen Lungenerkrankungen verglichen. Es zeigt sich, das nur die neue Methode den anatomischen Totraum richtig, d. h. unvergrosert, mist. Die gemessenen Volumina zeigen zudem die bei Lungengesunden vorhandene Korrelation zur Korpergrose. Es wird die Schwierigkeit der Definierung d…

Die Einführung der sogenanntenv-Koordinate als Variable für die Clearance-Kurven der Lunge zur Berücksichtigung der Variation der Atemfrequenz und des Atemzugvolumens

A New Type of Artificial Oxygen Carrier: Soluble Hyperpolymeric Haemoglobin with Negligible Oncotic Pressure—Production of Thermally Stable Hyperpolymers from Human Blood with Glutaraldehyde as Cross-Linker

Die Kooperativität bei der CO2-Hb-Bindung: Messungen mit Hilfe der 13C-NMR-Spektrometrie / The Cooperativity of the CO2 Hb Binding: Measurement by 13C -NMR Spectrometry

The detailed structure of the CO2 Hb binding curve is of considerable physiological interest, because the carbamino derivates, which are formed by the reaction of CO2 with Hb, are respon­sible for the well known Haldane effect. Under physiological conditions CO2 binds to the four terminal NH2-groups of the protein chains of Hb and it is generally assumed, that there exists no cooperativity between these groups. To examine whether this assumption is correct or not, we have measured the CO2Hb binding curve over a wide PCO2-range (from 0 kPa to about 70 kPa) by using 13C-NMR spectrometry. Morrow and coworkers (1976) have shown that carbamino-Hb causes a specific NMR signal. The quantitative an…