Effect of umbilical artery catheters on blood flow and oxygen supply to extremities

The effect of catheter placement in the abdominal aorta on the blood flow and oxygenation of lower extremities was evaluated in 30 New Zealand rabbits, weighing 0.55-3.5 kg, by inserting 3.5 and 5.0 French polyvinyl chloride catheters, of the type commonly used for umbilical artery catheterization, through the femoral artery, advancing 15-20 cm, and leaving in place for 10-30 min. Arterial blood pressure (BP), common iliac artery blood flow (BF), gracilis muscle tissue oxygen availability (O2a), and subcutaneous temperature (T) in the foot were continuously monitored before and during catheter placement and after withdrawal. There were no changes in the physiologic variables measured in the contralateral leg when the catheter remained below the aortic bifurcation; however, when the catheter was advanced 15-20 cm into the abdominal aorta, a decrease in lower extremity BF, O2a, and T occurred. Because the length of catheter insertion was maintained constant in each animal, the decreases in BF, O2a, and T are related to the relative dimensions of the vessel and the catheter. The ratio of catheter to vessel diamter, in addition to the site of catheter placement, should be considered during the clinical application of arterial catheters. Reduction in blood flow could be detected by continuous differential monitoring of core and extremity temperature or extremity muscle oxygen availability.     

Effect of chlordiazepoxide on schedule-controlled responding and schedule-induced drinking

Polyovular follicles and polynuclear ova have been recorded to occur only in 5 goats out of 24 goats of ages between 2 months 24 days and 5 years 2 months 18 days, studied. These structures were recognized at proestrus, estrus and metestrus only but never in the animals over 1 year of age. Polyovular and polynuclear follicles with no apparent degenerative changes were seen at estrus whereas degenerating ones were commonly seen at proestrus and metestrus also.     

Pseudocysts of the adrenal glands in newborn infants

With diagnostic aims the author used direct laryngeal tomography in patients with median stenosis of the larynx. Tomography made it possible to define the width of the lumen of the sumplica area. Depending on the change of the subplica area the author varied the extent of surgical intervention. He used the extralaryngeal method of vocal plica laterification in all patients. With narrow subglottis he practiced complete mobilization of the elastic cone and its subsequent laterification; with wide subglottis he mobilized only the uper edge of the elastic cone. He succeeded in obtaining good functional results concerning respiration in all patients.     

Formation of ectopic stimulation in the heart under the action of aconitine. I. The dynamics of input and output membrane currents

Rapid sodium and slow input and output currents were studied by the double saccharose bridge method on isolated atrial trabeculae of Rana ridibunda under the effect of aconitin (100 mg/l). It is shown that the ptroperties of rapid sodium channels change under the effect of aconitin. As the result of this, activation of the input sodium current begins at potentials which are close to the rest potential, the maximum value of sodium conduction reduces, while the reverse potential for sodium current is shifted in the direction of lower potentials. Despite the effect of aconitin, the sodium current is blocked by tetrodotoxin (10-6M). Aconitin causes reversible reduction of the input calcium current but has no effect on the output current.     

Association of crescentic glomerulonephritis with membranous glomerulonephropathy: a report of three cases

Association of membranous glomerulonephropathy with crescentic glomerulonephritis is apparently extremely rare. We report three patients who had this combination. One patient had biopsy-proven membranous glomerulonephropathy thirteen months prior to sudden and rapid decline in renal function necessitating hemodialysis. A repeat renal biopsy showed a superimposed crescentic nephritis and antiglomerular (GBM) antibodies were demonstrable in the serum. A second patient had proteinuria of unknown duration and then developed renal failure. Renal biopsy showed crescentic nephritis with a fine granular glomerular immunofluorescence for IgG typical of membranous glomerulonephropathy. Anti-GBM antibodies were present in this patient's serum. The third patient presented with acute renal failure of moderate severity. A renal biopsy revealed crescentic nephritis, granular deposits of immunoglobulins, and epimembranous electron-dense deposits typical of membranous glomerulonephropathy. Although his creatinine clearance improved spontaneously, nephrotic syndrome has persisted and a repeat renal biopsy showed a progression of the membranous glomerulonephropathy with the disappearance of the crescentic lesions. The reason for this peculiar association of membranous glomerulonephropathy and crescentic glomerulonephritis is unclear. It is possible that deposition of immune-complexes along glomerular basement membrane may render the glomerulus more susceptible to additional injury from a variety of other agents. Alternatively, depostis formed in one disease could initiate release of normal or altered basement membrane material and lead to formation of anti-GBM antibodies and subsequent development.     

Change in the concentration of total lipids, phospholipids and neutral lipids in rat liver mitochondria and microsomes during chemical carcinogenesis

Sharp increase in the content of total lipids and, especially, neutral lipids, and considerable decrease in the content of phospholipids were observed in liver microsomes and mitochondrias from liver of tumour-bearing rats in the process of the growth of sarcoma, induced by a single injection of 3,4-benzpyrene. The injection of anthracene, a non-cancerogenous hydrocarbon, practically did not affect the lipid composition of rat liver subcellular particles. Thus, the disturbances in normal functioning of subcellular particles under cancerogenesis are due to considerable change in the chemical composition of biomembranes. The data obtained confirm our hypothesis on lipid mobilization under tumour growth.     

Cholinergic innervation of vessels of the base of the brain

Distribution and activity of acetylcholinesterase in the intramural nerve apparatus of vessels of the base of the bran have been studied with the histochemical method of Koelle-Gomori. On the whole, 268 arteries have been examined. The activity of the ferment is detected in the effector nerve fibers in the wall of all cerebral vessels constituting the system of the circle of Willis. The periarterial nerve apparatus of cerebral arteries of the anterior and posterior regions of the circle of Willis consists of two cholinergic plexuses - superficial and deep plexus forming a multilayered neural cover. The terminal parts of cholinergic nerve fibres at the border with the muscular coat show a granular structure. Moreover, nerve cells rich in active ferment are found in the cholinergic plexuses. Difference in the character of cholinergic innervation of vessels of the internal carotid and the vertebrobasilar region has been shown. The obtained data indicate that the vessels of the circle of Willis possess a reliable cholinergic system of nerve regulation which along with other systems, such as that of adrenergic nerve fibers, maintains the homeostasis of the cerebral blood flow.