scholarly journals The bronchial vascular system in the dog

1931 ◽  
Vol 109 (762) ◽  
pp. 214-228 ◽  
Keyword(s):  
Vascular System ◽  
Early Stage ◽  
Preliminary Investigation ◽  
Systemic Circulation ◽  
Bronchial Tree ◽  
Bronchial Arteries ◽  
Arterial Blood ◽  
Two Systems ◽  
Chief Interest ◽  
The Moment

The distribution of the bronchial arteries (the vasa nutritia of Reisseissen) within the lung has been investigated by many anatomists but, beyond our knowledge that they are nutritional vessels to the bronchial tree (Reisseissen and Sömmering, 1808; Reisseissen, 1808, 1822 ; Luschka, 1863; Königstein, 1903), little is known of their significance for the maintenance of the normal functions of the lungs. At the moment their chief interest lies in the number of reports describing the changes in the bronchial blood vessels resulting from interference with the pulmonary vascular system and from lesions in the lungs. Two years ago Professor E. B. Verney and one of us (I. de B. D.) were conducting experiments in this laboratory which involved the separation of the pulmonary from the systemic circulation in the dog, the two systems being perfused by separate pumps. In one experiment it appeared that blood was being transferred from the aorta to the left auricle through the bronchial vascular system. It became desirable, therefore, to inquire into the conditions which govern the bronchial blood supply. At an early stage in this inquiry it was evident that, owing to the variations in the origin of the bronchial arteries, a study of the gross and minute anatomy of the bronchial vascular system in each perfusion experiment would be necessary if anything approaching a correct interpretation of our results was to be expected. As a preliminary investigation to our perfusion experiments, we have examined the bronchial vascular system in a number of animals and the results form the subject of this paper. In it are also incorporated the anatomical findings on the perfused lungs used for physiological investigations. We have concentrated our efforts on two main issues: the first, the arrangement of the bronchial arteries and veins with a view to setting up apparatus for perfusion of the bronchial arteries and the collection of the blood from the bronchial veins ; the second, an enquiry into possible arterial and venous communications between the bronchial and pulmonary vascular systems. It is clear that if arterial anastomotic channels exist between the two systems it will not be possible to separate completely the arterial blood of each.

scholarly journals V. The physiology of sugar in relation to the blood

1878 ◽  
Vol 26 (179-184) ◽  
pp. 314-321
Keyword(s):  
Carotid Artery ◽  
Natural Condition ◽  
Royal Society ◽  
Vascular System ◽  
Arterial System ◽  
Post Mortem ◽  
Arterial Blood ◽  
True Condition ◽  
The Moment ◽  
The Right

In a communication published in the ‘Transactions of the Royal Society ’(1860, p. 579) I gave the results of analyses showing that what had previously been looked upon, under Bernard’s glycogenic theory, as the natural condition of the blood in relation to sugar was a fallacious representation due to a post mortem change being allowed to exert its influence. It had hitherto been asserted that the blood of the right side the heart was in a notably different condition as regards the amount of sugar it contained from that of the arterial system, an error which I discovered arose from the non-observance of certain precautions in the mode of obtaining the blood for examination from the respective parts of the vascular system. Whilst the arterial blood had been collected during life, it was customary to collect that from the right side of the heart, without any special haste, after the destruction of the life of the animal. During the period thus allowed to elapse between the moment of death and the collection of the blood, an alteration occurs from the post mortem production of sugar in the liver, which causes the blood to assume an extent of saccharine impregnation which does not naturally belong to it during life, and which had faded to be recognized in its true light. I gave analyses which show that what was formerly taken as representing he natural condition of the blood of the right side of the heart furnished from .50 to .94 per cent., or, as it is more convenient to state it, 5.0 to 9.4 per 1000 of sugar, the blood from the carotid artery of the same animals, collected during life, having contained what I described as a trace of sugar. Other analyses, three in number, were given, representing the true condition of the blood belonging to the right side of the heart during life, and the results indicated from .47 to .73 per 1000 as the amount of sugar. Bernard has recently published some communications entitled “Critiques expérimentales sur la glycémaie,” in the Comptes Rendus de I’Académie des Sciences de Paris. His statements are founded upon a method of analysis which is not only strikingly devoid of precision as a quantitative analytical process, but in itself of a nature calculated to give rise to a fallacious result.

scholarly journals A closed-circuit heart-lung preparation.—Effect of alterations in the peripheral resistance and the capacity of the circulation

1926 ◽  
Vol 99 (697) ◽  
pp. 306-325 ◽  
Keyword(s):  
Vascular System ◽  
Superior Vena ◽  
Venous Pressure ◽  
Peripheral Resistance ◽  
Vena Cava ◽  
Systemic Circulation ◽  
Arterial System ◽  
Diastolic Filling ◽  
Arterial Blood ◽  
Lung Preparation

Investigations of “resistance” and “capacity” effects in relation to the control which they exert upon the vascular system have been carried out by many physiologists, notably by Weber (1), Volkmann (2), Donders (3), de Jager (4), Bayliss and Starling (5), and L. Hill (6, 7). According to Weber, the rise in arterial blood pressure due to arteriole vaso-constriction is caused by an increase in peripheral resistance and by a diminution in the capacity of the circulation. Bayliss and Starling (5) brought forward evidence in favour of this view and pointed out that the venous pressure was in part determined by a balance between these two factors. In opposition to Weber’s view, L. Hill and Barnard (6) hold that capacity changes have no effect on the venous pressure since the vascular system is not filled to distension. In a later paper L. Hill (7) states that reduction in the capacity of the splanchnic area is of importance in so far as it increases the diastolic filling, and so the output of the heart, but that the mean hydrostatic pressure cannot be considered to contribute to this result. The part played by constriction of the veins in altering the venous and arterial pressure is discussed in a paper by Connet (8) in which a full bibliography is given. In a paper published in the ‘ Journal of Physiology ’ (9) I described a modification of Starling’s heart-lung preparation, in which the blood circuit was converted to a closed system, so as to imitate more closely the conditions ruling in the animal body, while maintaining the various factors fully under control of the experimenter. The arrangement is shown in fig. 1. The blood from the aorta flows through a cannula placed in the brachio-cephalic artery (A), the velocity of flow being recorded by a Pitot tube (B) or by a Henderson’s cardiometer. The peripheral resistance is regulated by a compressible fingerstall (D), a second resistance (D') being inserted for studying the effects of shunt circuits. The blood then passes to the venous reservoir (K) which consists of a rubber bag of approximately 250 c.c. capacity. The distal end of the venous reservoir is connected to the superior vena cava. A finger-stall (C) joined by a side tube to the arterial system represents the elasticity of the arterial sytem ; this finger-stall and the venous reservoir K when enclosed in plethysmographs enable the experimeter to study alterations in the volume of the systemic circulation.

Improving website accessibility for people with early-stage dementia: A preliminary investigation

2005 ◽  
Vol 9 (5) ◽  
pp. 442-448 ◽  
Author(s):  
Ed Freeman ◽  
Linda Clare ◽  
Nada Savitch ◽  
Lindsay Royan ◽  
Rachael Litherland ◽  
...  
Keyword(s):  
Early Stage ◽  
Preliminary Investigation

Preliminary investigation on the use of low current pulsed power Z-pinch plasma devices for the study of early stage plasma instabilities

2017 ◽  
Vol 60 (1) ◽  
pp. 014031 ◽  
Author(s):  
E Kaselouris ◽  
V Dimitriou ◽  
I Fitilis ◽  
A Skoulakis ◽  
G Koundourakis ◽  
...  
Keyword(s):  
Early Stage ◽  
Preliminary Investigation ◽  
Pulsed Power ◽  
Plasma Instabilities ◽  
Pinch Plasma ◽  
Z Pinch

Arterial pressure contour analysis for estimating human vascular properties

1976 ◽  
Vol 40 (2) ◽  
pp. 171-176 ◽  
Author(s):  
T. B. Watt ◽  
C. S. Burrus
Keyword(s):  
Cardiac Cycle ◽  
Vascular System ◽  
Model Parameters ◽  
Pressure Curve ◽  
Contour Analysis ◽  
Order Model ◽  
Third Order ◽  
Arterial Blood ◽  
Pressure Contour ◽  
Multiple Measurements

The form of an arterial blood pressure curve during the diastolic portion of the cardiac cycle was here employed to identify parameters in a third-order model of the vascular system. Calculated elastic and intertial characteristics of this fitted model then became clinically accessible indices of corresponding real vascular properties. This technique incurred no risk and little discomfort for the patient. Tested in theory, in animal experimentation, and in human observations, our procedure utilized a Gauss-Newton algorithm via digital computer to provide rapid model solutions from different starting values, from multiple measurements sites, and from normal or diseased patients. Model parameters thus determined defined ranges of normal variation and suggested a less compliant arterial bed in hypertensive than in normotensive patients.

scholarly journals Palate: The App for Finding Restaurant Faster

2021 ◽  
Author(s):  
Patrick Gioseffi
Keyword(s):  
Mobile Application ◽  
Early Stage ◽  
Design Principles ◽  
Major Research ◽  
Research Project ◽  
On Demand ◽  
Current Process ◽  
The Moment ◽  
The Impact

This Major Research Project (MRP) aims to investigate the impact of the on-demand economy, millennials’ digital habits, and the emergence of super apps on the restaurant-finding process. Currently, restaurant-goers are presented with multiple specialty applications to complete different tasks when evaluating restaurants. The current process of deciding on a restaurant is both time-consuming and inefficient. This project aims to propose a solution to this problem in the form of an early-stage super app called Palate. Palate is a mobile application that aims to streamline the process of discovering restaurants from the moment a restaurant-goer begins their search to the moment they confirm a reservation. This paper will discuss design principles, theories of the on-demand economy, restaurant-goers digital habits, super apps and the rationale for designing a restaurant super app interface.

scholarly journals Observations on the Nutrition of Maggots of Australian Blow-Flies

1933 ◽  
Vol 10 (3) ◽  
pp. 237-246
Author(s):  
M. J. MACKERRAS ◽  
M. R. FRENEY
Keyword(s):  
Early Stage ◽  
Wool Fibre ◽  
Initial Growth ◽  
Full Development ◽  
Adequate Food ◽  
Acid Reaction ◽  
Keratin Hydrolysis ◽  
The Moment ◽  
The Masses ◽  
Two Stages

1. Larvae of L. cuprina and Ch. rufifacies are capable of liquefying and digesting protein media without the intervention of bacteria. Both species and L. sericata secrete tryptic and peptic enzymes and at least L. cuprina does so from the moment of hatching. Tryptase is more abundant than peptase. Predatory activity, though a normal habit of Ch. rufifacies, is not necessary for any of these species and did not occur in the masses of Lucilia larvae used for extraction of the enzymes, although they were kept for periods up to 24 hours without food. 2. Partial development of larvae occurred in sheep dung, faeces-stained wool and in the products of keratin hydrolysis. Complete development took place in wool containing a "gummy crust" of dried exudate and in some samples of faeces-stained wool. Some of the samples of faeces-stained wool and those containing a "crust" have been demonstrated serologically by Dr I. M. Mackerras to have an increased content of soluble sheep protein as compared with normal wool. A marked increase of soluble protein has been demonstrated in struck wool both chemically and serologically. 3. Moisture, warmth, shelter and aeration are essential physical conditions for larval development. In addition, an alkaline reaction is relatively favourable and an acid reaction relatively unfavourable. 4. There are normally two stages in the development of a primary strike, the first stage being from hatching up to the time the larvae attack the skin, the outer layer or epidermis of which is approximately 36µ thick (Whitnall, 1931). During this stage they must feed, if at all, on materials already present. The second stage is from the commencement of an actual skin lesion up to full development of the maggots. During this stage there is a more or less copious serous exudation, which has been shown to be an adequate food for the full development of the maggots. Faeces-staining, presence of exudate due to a prior lesion, and products of wool hydrolysis have been shown to be adequate to carry the larvae through the first stage. Wool hydrolysis on the living sheep is probably not an important factor, judging by an examination of wool samples, but we have isolated organisms which, when growing on a nutrient medium, are capable of disintegrating wool fibre. 5. The rôle of bacterial activity in strike is complex and appears to be substantially as follows: (a) to produce substances which attract the flies and stimulate them to oviposit; (b) to provide food for the initial growth of the maggots, either by rendering assimilable the inert proteins, or by causing a skin reaction with a serous exudation. 6. The immediate work for the future is a more exact determination of: (a) the nature of the food of the larvae in the early stage of growth on the living sheep; (b) the factors which influence its production; and (c) the mechanism by which the larvae invade the skin.

The Generation of Kinins in the Blood of Dogs during Hypotension Due to Haemorrhage

1970 ◽  
Vol 39 (3) ◽  
pp. 349-365 ◽  
Author(s):  
H. E. Berry ◽  
J. G. Collier ◽  
J. R. Vane
Keyword(s):  
Blood Pressure ◽  
Time Course ◽  
Venous Pressure ◽  
Venous Blood ◽  
Systemic Circulation ◽  
Substantial Effect ◽  
Mixed Venous Blood ◽  
Shed Blood ◽  
Arterial Blood ◽  
Organ Technique

1. Circulating kinins were detected and continuously assayed during hypotension due to haemorrhage in dogs, using the blood-bathed organ technique and isolated strips of cat jejunum as the assay tissue. 2. In arterial blood kinin concentrations of 1–5 ng/ml were attained after a hypotension of 35–65 mmHg had been maintained for 10–190 min. When portal venous blood was simultaneously assayed kinins appeared earlier and in concentrations 1–2 ng/ml higher than in arterial blood. No differences in time course of kinin generation or in concentration were found when mixed venous blood and arterial blood were compared. In those instances in which the blood pressure was restored to normal by returning the shed blood, kinin formation stopped. 3. Kinin generation was due to the presence in the circulation of a kinin-forming enzyme, such as kallikrein. When kallikrein was infused into the portal vein, it was partially inactivated by the liver. 4. Prolonged intravenous infusions of kallikrein (20–60 mu kg−1 min−1) generated kinins in the circulation in concentrations (1–5 ng/ml) which were well maintained throughout the infusion, demonstrating that kinin generation is not limited by depletion of the precursor kininogen; nevertheless, the effects of kallikrein infusions on the blood pressure and central venous pressure waned. 5. It is concluded that in hypotension due to haemorrhage, an active kallikrein appears in the portal circulation. Delay in the appearance of kallikrein in the systemic circulation may be due to the kallikrein inactivating mechanism of the liver. This inactivating mechanism may fail during shock. Kinins are generated in amounts sufficient to have a substantial effect on the circulation and an influence on the course of events in shock.

scholarly journals Lethal avian influenza A (H5N1) virus induces ataxic breathing in mice with apoptosis of pre-Botzinger complex neurons expressing neurokinin-1 receptor

2017 ◽  
Vol 313 (5) ◽  
pp. L772-L780 ◽  
Author(s):  
Jianguo Zhuang ◽  
Na Zang ◽  
Chunyan Ye ◽  
Fadi Xu
Keyword(s):  
Respiratory Failure ◽  
Influenza A ◽  
Early Stage ◽  
Respiratory Rhythm ◽  
Body Weight Loss ◽  
Neurokinin 1 Receptor ◽  
Arterial Blood ◽  
Bötzinger Complex ◽  
Neurokinin 1 ◽  
Active Caspase

Lethal influenza A (H5N1) induces respiratory failure in humans. Although it also causes death at 7 days postinfection (dpi) in mice, the development of the respiratory failure and the viral impact on pre-Botzinger complex (PBC) neurons expressing neurokinin 1 receptor (NK1R), which is the respiratory rhythm generator, have not been explored. Body temperature, weight, ventilation, and arterial blood pH and gases were measured at 0, 2, 4, and 6 dpi in control, lethal HK483, and nonlethal HK486 viral-infected mice. Immunoreactivities (IR) of PBC NK1R, H5N1 viral nucleoprotein (NP), and active caspase-3 (CASP3; a marker for apoptosis) were detected at 6 dpi. HK483, but not HK486, mice showed the following abnormalities: 1) gradual body weight loss and hypothermia; 2) tachypnea at 2–4 dpi and ataxic breathing with long-lasting apneas and hypercapnic hypoxemia at 6 dpi; and 3) viral replication in PBC NK1R neurons with NK1R-IR reduced by 75% and CASP3-IR colabeled at 6 dpi. Lethal H5N1 viral infection causes tachypnea at the early stage and ataxic breathing and apneas (hypercapnic hypoxemia) leading to death at the late stage. Its replication in the PBC induces apoptosis of local NK1R neurons, contributing to ataxic breathing and respiratory failure.

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