bluuebunny/crossref_metadata_2025 huggingface dataset:
THE ABSORPTION OF PARTICLES BY THE LYMPHATICS OF THE DIAPHRAGM
Authors: French J. E. , Florey H. W. , Morris B.
Published: December 2014

The absorption of particles from the peritoneal cavity by the terminal lymphatics, or lacunes, of the rabbit's diaphragm has been studied with the light and electron microscopes. Absorption occurs predominantly through those parts of the peritoneal surface of the diaphragm which overlie the lymphatic lacunes. These parts are referred to as the lacunar roofs.

The mesothelial cells of the roofs have features which distinguish them from mesothelial cells elsewhere on the peritoneal surface of the diaphragm. The cells are more closely set, stain more darkly, and separate from each other more readily, particularly at the base of the intercellular junctions. They are supported by a lattice of coarse and fine fibres. In the meshes of this lattice mesothelial and lymphatic endothelial cells are separated only by the basement membrane of the mesothelium which in places may be incomplete.

Erythrocytes pass through the roof into the lumen of the lacune through gaps which are formed by separation of the mesothelial cells and of the endothelial cells at the intercellular junctions. Particles of India ink and colloidal particles of thorium dioxide and saccharated iron oxide enter the intercellular spaces of the mesothelium and spread freely within the meshes of the fibre lattice. These particles appear to pass through the mesothelium by a predominantly extracellular pathway and probably enter the lymphatic lumen through temporary channels which are formed by separation of endothelial cells at the intercellular junctions.

Absorbed colloidal particles accumulate in the cytoplasm of mesothelial and lymphatic endothelial cells in the roofs and a proportion of absorbed material may be transported intracellularly through these two layers in cytoplasmic vesicles. Lymphatic endothelial cells at other sites in the diaphragm can take up colloidal particles from the lumen of the lymphatics.
ABILITY OF AERATED LYMPH TO CONVERT VENOUS BLOOD INTO HÆMOSTATIC BLOOD
Authors: Cruz W. O. , Oliveira A. C. , de Meis L.
Published: December 2014

Previous studies using dog hind‐leg preparations showed that only arterial blood has hæmostatic activity, the venous blood rearterialized in vitro being non‐hæmostatic. This loss of hæmostatic activity when arterial blood reaches and passes the capillaries is observed regionally (jugular and hepatic veins) and in mixed venous blood (right auricle), which has received lymph from the thoracic duct. Hæmostatic principles may be lost through the capillaries, so lymph was tried as an hæmostatic agent when added to venous blood. Lymph after contact with air, even in small concentrations (0·25 ml. of ærated lymph in 100 ml. of venous blood), is able to convert venous blood into hæmostatic blood and has no effect on arterial blood. This ability of aerated lymph seems general, since cervical or jugular lymph is as able as thoracic duct lymph to convert venous into hæmostatic blood. Non‐aerated lymph has no effect in venous blood and has showed a strong inhibitory effect when mixed with arterial blood.

The significance of selective passage of plasma constituents in the capillaries and the role of oxygen are stressed when the mechanism of these effects of lymph is discussed.
THE MOLECULAR STRUCTURE OF ISOLATED AND INTRACELLULAR FERRITIN
Authors: Muir A. R.
Published: December 2014

The ferritin molecule consists of a central nucleus of high iron content, surrounded by a shell of protein approximately spherical in shape. This study with the electron microscope suggests that this iron is stored in six micelles arranged at the corners of a regular octahedron. This structure can be demonstrated in isolated crystallizable ferritin and it permits the identification of single molecules of ferritin in sections of tissues. The implications of an octahedral micellar form are discussed in relation to the shape of the protein coat and the crystal structure.
E.C.G. CHANGES IN DOGS COOLED AFTER HÆMORRHAGE
Authors: Pantelić D. , Vajs E. , Magazinović V. , Debijadji R.
Published: December 2014

Experiments have been done to determine the effect of hypothermia on dogs previously subjected to hypotension induced by hæmorrhage. After 1 hr. of hypotension two groups of dogs were cooled to 28° C. and 31° C. respectively and then left for 2 hr. at room temperature (24° C.). Seven out of nineteen died of ventricular fibrillation. On rewarming six more died after some hours. The E.C.G. (Lead II) changes during hypothermia were much the same as those found in cooled normal dogs. The E.C.G. changes due to hæmorrhage were similar to those found in dogs subjected to hæmorrhage at normal temperatures superimposed on the hypothermic E.C.G. patterns. Below 25° C. it was sometimes difficult to decide on the relative preponderance of the two effects. The only difference between survivors and those dogs which died was the greater incidence of the “Osborn wave” in the E.C.Gs. of the latter. However, there is no evidence that the appearance and behaviour of this wave can be taken either as a sign of a poor prognosis or as a warning of impending ventricular fibrillation.
CHANGES IN ERYTHROCYTE AMINO NITROGEN FOLLOWING EXPERIMENTAL MUSCLE LESIONS IN CHICKS
Authors: Bell D. J. , Siller W. G.
Published: December 2014

Adrenocorticotrophin (ACTH) in 16 per cent gelatin, 16 per cent gelatin alone, cortisone acetate suspended in a solution of sodium carboxymethyl cellulose or the latter solution alone, all produced temporary localized lesions at the site of injection into the pectoral muscle of 5‐week‐old fowls. The lesions, which were most severe in the instance of the gelatin injection, and which varied somewhat from bird to bird, were characterized by (a) inflammatory œdema and infiltration by heterophils, (b) Zenker's degeneration of the muscle fibres, (c) healing and regeneration. The gelatin‐induced lesions showed marked lymphoid hyperplasia. Healing took place usually around 7–10 days after the last injection. In some instances it must have occurred more rapidly.

During the period while the lesions were sufficiently severe to be detected macroscopically, the levels of non‐protein nitrogen (NPN) and ninhydrin‐positive amino nitrogen (NN) in both plasma and erythrocytes diverged considerably from the values found before injection and after the wound had healed. Lesions produced by both gelatin and long‐acting ACTH were followed by little or no change in the erythrocyte‐NPN but the NN of these cells was considerably raised. Lesions induced by the suspension of cortisone acetate were followed by only minor changes in the erythrocyte NN, with little or no concomitant change in the erythrocyte NPN. Lesions produced by the medium used to suspend the cortisone acetate were followed by a marked fall in the erythrocyte NN.

There were no consistent changes in the plasma NN, but the overall effect was one of a fall in NN.

The results are discussed in relation to some known effects of trauma in mammals.
THE CORRELATION OF THYROID FUNCTION WITH THE RATE OF OXYGEN UPTAKE OF HUMAN LEUCOCYTES
Authors: Alexander W. D. , Bisset Sheenah K.
Published: December 2014

The rate of oxygen uptake of leucocytes from patients with different degrees of thyroid activity was studied, and it was shown that there is a direct relationship between the oxygen uptake of leucocytes and the BMR of the patient. The leucocytes from hyperthyroid patients had an oxygen uptake of 0·185±0·037 µM./hr./107 cells. Leucocytes from euthyroid people had an oxygen uptake of 0·119±0·021 µM./hr./107 cells. The leucocytes from myxœdematous patients had an oxygen uptake of 0·083±0·016 µM./hr./107 cells.

The effect of treatment on the oxygen consumption of leucocytes from three patients with myxœdema and three with hyperthyroidism was then investigated. The hyperthyroid patients were treated with 131I and after therapy there was a decrease in the oxygen consumption of the leucocytes. In the three patients with myxœdema, the oxygen consumption of the leucocytes increased after thyroxine therapy.
A COMPARISON OF THE OXYGEN DISSOCIATION CURVES OF THE BLOODS OF MATERNAL, FETAL AND NEWBORN SHEEP AT VARIOUS pHs
Authors: Meschia Giacomo , Hellegers Andre , Blechner Jack N. , Wolkoff A. Stark , Barron Donald H.
Published: December 2014

Oxygen dissociation curves of the bloods of pregnant sheep, fetal and newborn lambs have been prepared at plasma hydrogen‐ion concentrations in the physiological range. At pH 7·4, the fetal blood was half saturated at about 16·0 mm.Hg oxygen pressure. The maternal oxygen dissociation curves of the blood different animals showed variability in their positions; half saturation occurred at values of oxygen pressure ranging from 31·6 to 37·5 mm. Hg. The curves bloods of newborn lambs had positions intermediate between fetal and adult types.
PROPERTIES OF THE ERYTHROCYTES OF TWO MARSUPIALS: THE BRUSH‐TAIL POSSUM, TRICHOSURUS VULPECULA (KERR) AND THE QUOKKA, SETONIX BRACHYURUS (QUOY & GAIMARD)
Authors: Barker Jennifer M.
Published: December 2014

In possums from one area of Australia, “high potassium” (HK) erythrocytes were smaller in volume, more fragile osmotically and contained smaller amounts of hæmoglobin and higher concentrations of (Na + K) than “high sodium” (LK) erythrocytes. The cells of HK possums from a second area were less fragile than those of HK possums from the first area. The differences in osmotic fragility were related to differences in shape. Concentrations of water and hæmoglobin were similar in all types of cell.

In quokkas (wallabies)—whose erythrocytes contain roughly equal concentrations of Na and K—osmotic fragility tests and measurements of erythrocyte diameter did not indicate that the blood contained two types of cells differing markedly in these properties.
THE DISPERSAL OF FLUID IN CONNECTIVE TISSUE AND ITS MICRO‐ANATOMICAL IMPLICATIONS
Authors: Day T. D.
Published: December 2014

Local injection of 30 cu. mm. paraffin (BP. 162° C.) into mouse subcutaneous connective tissue at a pressure of 5 cm. H2O was followed by reflux of almost the whole amount when the pressure was reduced to 0. The compression resulting from this transitory injection initiated a movement of tissue fluid which was at first diffuse but ended in the filling of the main lymphatic vessels. Further compression was followed by greater extension even to the regional lymphatic gland. This phenomenon is not compatible with the concept of connective tissue as a system of cells and fibres embedded in a homogeneous ground substance. It does however add support to the belief that the tissue is essentially membranous.
AN ANALYSIS OF ACTIVE AND PASSIVE EFFECTS ON THE PULMONARY VASCULAR BED IN RESPONSE TO PULMONARY NERVE STIMULATION
Authors: de Burgh Daly I.
Published: December 2014

In an isolated innervated perfused left lung preparation of the dog the calculated pulmonary vascular resistance overlapped the upper limit of the range reported by others for normal resting animals.

The increase in pulmonary vascular resistance in response to stimulation of pulmonary nerves in which pulmonary vasoconstrictor fibres and bronchoconstrictor fibres are intermingled was due to vasoconstriction in the pulmonary vascular bed proper. This response was not appreciably altered or influenced by passive effects due to accompanying bronchoconstriction or changes in the bronchial circulation.
OBSERVATIONS ON SUBCUTANEOUS MACROPHAGES. PHAGOCYTOSIS OF IRON‐DEXTRAN AND FERRITIN SYNTHESIS
Authors: Muir A. R. , Golberg L.
Published: December 2014

The structure of macrophages at the site of subcutaneous injections of iron‐dextran has been studied with the electron microscope. Iron‐dextran has a macromolecular structure which can be distinguished from that of its metabolic product, the iron‐storage protein ferritin. By a process of pinocytosis the macrophages ingest iron‐dextran, then concentrate it within cytoplasmic vacuoles, apoferritin is synthesized and the iron is finally stored within this protein to form ferritin. At first individual molecules of ferritin are uniformly distributed throughout the cytoplasm, accompanied by a few molecules in the nucleoplasm but, as a rule, none in mitochondria. One week after injection, vacuoles containing a mixture of iron‐dextran and ferritin are found, and these are gradually replaced by vacuoles containing only ferritin.
THE EFFECT OF MAINTAINED AMMONIUM CHLORIDE ACIDOSIS ON THE RELATION BETWEEN PULMONARY VENTILATION AND ALVEOLAR OXYGEN AND CARBON DIOXIDE IN MAN
Authors: Cunningham D. J. C. , Shaw D. G. , Lahiri S. , Lloyd B. B.
Published: December 2014

Five men ingested about 12 g. NH4Cl daily for about a week. Acidæmia was assessed by measuring plasma (HCO3) and alveolar pCO2. Before, during and after the period of ingestion the subjects were given various gas mixtures to breathe, and pulmonary ventilation (V) and the alveolar gas pressures (pCO2, pO2) were measured in the steady state. The effect of acidæmia on the parameters of the equation was examined. Only B, which is related to the “CO2‐threshold”, was consistently changed, being reduced in acidæmia.
A COMPARISON OF THE OXIDATION OF CHOLESTEROL‐26‐14C, PALMITATE‐1‐14C AND TRIPALMITIN‐1‐14C BY MACROPHAGES IN VITRO
Authors: Day A. J.
Published: December 2014

The oxidation by macrophages of cholesterol‐26‐14C to 14CO2 was compared with the oxidation by macrophages of 14C‐labelled fatty acids (sodium palmitate‐1‐14C) and 14C‐labelled triglycerides (artificial emulsion of tripalmitin‐1‐14C and chyle containing tripalmitin‐1‐14C). Cholesterol was presented to rabbit macrophages in vitro as an aqueous solution (using Tween 20 to disperse the cholesterol), as an aqueous suspension and as cholesterol contained in chylomicra in rat chyle. It was shown that appreciable oxidation of 14C‐labelled fatty acids and triglycerides could be brought about by macrophages but under similar circumstances no oxidation of the cholesterol side‐chain could be demonstrated in any of the preparations used.

The failure of the macrophages in vitro to oxidize cholesterol probably reflects their behaviour in vivo with cholesterol taken up by macrophages in the arterial wall. The oxidation of other lipids by these cells and their failure to deal with cholesterol may then be associated with cholesterol deposition and with the pathogenesis of atheroma.
THE ABSORPTION OF BOUND FORMS OF B‐GROUP VITAMINS BY RAT INTESTINE
Authors: Turner J. B. , Hughes D. E.
Published: December 2014

The rates of movement of bound forms of B‐group vitamins (coenzyme A, thiamine pyrophosphate, diphosphopyridine nucleotide, flavin mononucleotide and biocytin) from the mucosal to serosal fluids has been measured in everted sacs of rat jejunum. Thiamine pyrophosphate, biocytin and flavin mononucleotide move at approximately the same rates as the free vitamin: there was no indication of active transport. The results thus resemble those obtained with free vitamins alone and suggest that these bound forms are absorbed by passive diffusion. Diphosphopyridine nucleotide, coenzyme A and, to a lesser extent, flavin mononucleotide were rapidly degraded to free forms of the vitamins. The breakdown of the pyridine nucleotide was studied in cell‐free extracts of intestinal mucosa and has been shown to be due mainly to a DPN'ase type of enzyme, although a nucleotide pyrophosphorylase is also present. Some breakdown of biocytin to form free biotin was also found. Negligible breakdown of thiamine pyrophosphate was detectable under these conditions.
THE CHEMICAL COMPOSITION OF ADIPOSE TISSUE OF MAN AND MICE
Authors: Thomas Lorette W.
Published: December 2014

The chemical composition of human and mouse adipose tissue taken from fat and thin individuals has been determined.

The tissues were obtained from the epididymal fat pads of fat, lean and normal strains of mice and from sixty‐one human subjects undergoing various abdominal operations. In both the mice and the humans, the adipose tissue from obese individuals contained slightly more fat and less protein and water than that from lean individuals. However, the differences were small and it is concluded that obese individuals contain, in their total adipose tissue, much more non‐fatty cellular material than do the lean.
FATTY ACID TRANSPORT IN THORACIC DUCT, HEPATIC AND INTESTINAL LYMPH DURING FASTING AND AFTER FEEDING GLUCOSE
Authors: Coxon R. V. , Robinson D. S.
Published: December 2014

Analyses of thoracic duct lymph in the rat during fasting and after glucose feeding have shown the presence of esterified fatty acids additional to those which are contributed to the lymph by plasma lipoprotein lipid. The excess may amount to an output in thoracic duct lymph of 50 mg. esterified fatty acid a day. In the dog, analyses of hepatic and intestinal lymph during fasting have shown that excess esterified fatty acid is present in intestinal, but not hepatic, lymph.

Calculations based on these findings do not support the view that the lymnphatics are a major route for the mobilization of fatty acid during fasting.
THE PROJECTION OF THE BINOCULAR VISUAL FIELD ON THE OPTIC TECTA OF THE FROG
Authors: Gaze R. M. , Jacobson M.
Published: December 2014

The projection of the binocular visual field on the optic tecta of Rana temporaria has been mapped by recording action potentials evoked in the tectum by a spot of light in the visual field. The binocular visual field extends for about 100° on the horizontal meridian. Only the central region of the binocular field is represented through both eyes on both ipsilateral and contralateral tecta. The binocular field to the left and right of this central region is represented through both eyes on one tectum only: the left side of the field projects through both eyes to the right optic tectum, while the right side of the field projects through both eyes to the left tectum. Corresponding retinal points project to the same tectal locus.
THE CHANGING STATE OF BREATHING DURING INHALATION OF CO2, STUDIED WITH AN INEXPENSIVE, RECORDING CO2‐ANALYZER
Authors: Anderton J. L. , Harris E. A.
Published: December 2014

A method is described for recording alveolar CO2 tension using simple and inexpensive apparatus. The changing state of hyperventilation due to CO2 has been studied and a procedure devised for deriving the steady‐state CO2‐response line from data obtained during the changing state. This procedure has considerable practical advantages over conventional methods. Evidence is presented to show that the time needed for equilibration of CO2 between the arterial blood and the cells of the respiratory centre is of the order of 4 min.
ARTERIOLAR NECROSIS AND THE PRENECROTIC PHASE OF EXPERIMENTAL HYPERTENSION
Authors: Gardner D. L.
Published: December 2014

A serial study has been made of arteriolar lesions in hypertensive rats. Following left nephrectomy, deoxycortone acetate implants lead to systemic hypertension when animals are given 1 per cent NaCl to drink. Rising blood pressure is accompanied by cardiac enlargement, compensatory renal hypertrophy, polydypsia and polyuria. These changes are detected within 3–7 days of operation. Not until 16–18 days after operation, however, is there histological evidence of the focal necrosis of visceral arterioles characteristic of rat hypertension. Early arteriolar injury is first recognized by the presence of Schiffpositive material. Only when arteritis supervenes is there evidence of an altered distribution of vascular alkaline phosphatase and 5‐nucleotidase and of a change in the medial uptake of arteriolar 35SO4. The period preceding arteriolar necrosis is termed the prenecrotic phase of hypertension.
PULMONARY CHEMORECEPTORS
Authors: Duke Helen N. , Green J. H. , Heffron P. F. , Stubbens V. W. J.
Published: December 2014

The existence of a chemoreceptor mechanism supplied by the pulmonary artery was demonstrated in the following manner.

In anæsthetized cats or rabbits the main pulmonary artery was cannulated through the right ventricle. The right pulmonary artery was tied and the left pulmonary artery cannulated approximately 0·5 cm. from the bifurcation. The isolated pulmonary segment was perfused at normal pressure and rate of blood flow. Reflex effects on respiration and sympathetic nervous efferent activity were studied by simultaneous perfusion of the systemic circulation at normal pressure and flow rate.

Perfusion of the isolated pulmonary arterial segment with added NaCN caused increased afferent vagal activity. When the systemic circulation was perfused simultaneously and independently of the pulmonary arterial segment, anoxia or asphyxia of the pulmonary arterial perfusate caused reflex increase in the rate and depth of respiration and sympathetic activity. Hypercapnia of the pulmonary arterial blood had little effect in the presence of a high oxygen tension.
THE EFFECT OF HYDROCHLOROTHIAZIDE ON THE KIDNEY OF THE ELECTROLYTE‐DEFICIENT RAT
Authors: Kennedy G. C. , Parker R. A.
Published: December 2014

In rats eating a normal diet, large doses of hydrochlorothiazide given for 6 weeks caused potassium depletion with only localized changes in the kidney. With an electrolyte‐deficient diet much smaller therapeutic doses of the drug caused severe kidney damage in 10 days. The severe type of lesion seemed less likely to be due to increased potassium depletion than to potentiation of its effect by other electrolyte deficiencies.

Hydrochlorothiazide‐induced lesions had some features in common with potassium deficiency induced by other means, especially a striking enlargement of the intercalated cells of the first part of the collecting duct. This suggests that these cells may be concerned in the tubular secretion of potassium. Hydrochlorothiazide diminished the widespread epithelial hyperplasia of renal tubules caused by deoxycortone without reducing the enlargement of the intercalated cells which also followed steroid treatment. This may have been due to partial blockade of the tubular action of the deoxycortone.
A COMPARISON OF THE OXYGEN AFFINITY OF MATERNAL AND FETAL BLOOD OF THE MACACA MULATTA
Authors: Behrman Richard E. , Heller Christopher J. , Battaglia Frederick C. , Hellegers Andre E.
Published: December 2014

Constants relating the oxygen tension, percentage oxygen saturation and pH in the blood of maternal and fetal Macaca Mulatta (Rhesus) monkeys have been determined. Half saturation of the blood with oxygen is obtained at PO2's of 27·0 and 16·0 mm. of mercury in maternal and fetal blood respectively, at pH 7·40. The effect of pH changes upon the oxygen dissociation curves, and the slopes of these curves, were found to be identical in maternal and fetal blood. A comparison of the oxygen affinities of these bloods was made with those of other species, and the differences discussed.
FATTY ACID PATTERNS OF CHOLESTEROL ESTERS SYNTHESIZED BY RETICULO‐ENDOTHELIAL CELLS
Authors: Day A. J. , Fidge N. H. , Gould-Hurst P. R. S. , Risely D. J.
Published: December 2014

The fatty acid pattern of cholesterol esters synthesized by RE cells in rat lymph nodes was determined by gas phase chromatography. Following the uptake of cholesterol by these cells esterification with predominantly saturated fatty acids occurred. Where corn oil or coconut oil was administered together with the cholesterol the fatty acid pattern of the cholesterol esters synthesized became more unsaturated or more saturated respectively. The significance of these findings in terms of the metabolism of cholesterol by RE cells and its relevance to atherosclerosis is discussed.
ARTERIAL AND PORTAL VENOUS BLOOD FOR ESTIMATING MINERAL ABSORPTION IN THE CONSCIOUS SHEEP
Authors: Moodie E. W. , Walker A. I. T.
Published: December 2014

A method is described for estimating the absorption of nutrients in conscious sheep by comparing the composition of arterial and portal venous bloods. One hundred and seventeen pairs of samples were obtained from sixteen sheep (seven castrated male and nine female) and analyzed for hæmoglobin, plasma calcium, magnesium, inorganic phosphate, citric acid and whole‐blood chloride contents. Changes in the volume of the blood passing through the splanchnic area were estimated by comparing the hæmoglobin concentrations in arterial and portal blood samples.

The veno‐arterial differences in the concentration of each constituent before and after correction for changes in the volume of the blood are presented and the necessity for making this correction is discussed. There is evidence of differences in the rate of absorption of calcium and chloride between male and female sheep and among individual female sheep, and also of differences in the absorption of calcium and chloride compared with magnesium and inorganic phosphate.
AN ELECTRON MICROSCOPE STUDY OF THE PERIPHERAL NERVES OF THE HAGFISH (MYXINE GLUTINOSA, L.)
Authors: Peters A.
Published: December 2014

The peripheral nerves of the hagfish, Myxine glutinosa, L. have been studied by electron microscopy. These nerves are unmyelinated and each axon is separately enclosed by a sheath composed of single layer of Schwann cells, whose nuclei lie parallel to the long axis of the nerve. Usually each axon has its own individual sheath, but sometimes two axons, though separated, are ensheathed by the same Schwann cell. In transverse sections, the number of cells forming the sheath varies with the diameter of the axon; fibres of diameter 3 µ and less, have sheaths composed of a single Schwann cell, but a number of cells are present in the sheaths of the larger axons. Where adjacent Schwann cells come together, they are most commonly separated by a distance of about 120 Å, and this is the distance that separates the irregular inner surface of the Schwann cell sheath from the axolemma. The outer surface of each sheath is smooth and is separated from the collagen and reticulin of the endoneurium by a basement membrane.
ACID MUCOPOLYSACCHARIDE IN THE BRONCHIAL TREE IN THE MOUSE AND RAT (SIALOMUCIN AND SULPHATE)
Authors: McCarthy Ciaran , Reid Lynne
Published: December 2014

Staining with combined Alcian blue and periodic‐acid‐Schiff stains distinguishes the neutral (red staining) from the acid (blue staining) mucopolysaccharide. Neuraminidase digestion has been used to identify neuraminic acid and autoradiography, following the administration of radioactive sulphate, to trace sulphate.

All acid mucopolysaccharide in the mouse bronchial tree is neuraminidase susceptible; no uptake of radioactive sulphate is shown. In the rat there is a regional difference; in the epithelium of the peripheral airways only neuraminidase susceptible acid mucopolysaccharide is present, whereas in the trachea and main bronchi most of the cells contain acid mucopolysaccharide, take up radioactive sulphate and are not susceptible to neuraminidase. In the large intrapulmonary bronchi there are cells with either of the above characteristics, those with similar properties usually being grouped together.
THE NATURE OF THE WEIGHT GAIN INDUCED, BY PROGESTERONE IN MICE
Authors: Dewar A. D.
Published: December 2014

In free‐fed mice with progesterone tablet implants and in pseudopregnant mice, an increase in food consumption usually accompanies the body weight gain characteristic of progesterone stimulation; it is not, however, an essential feature since mice on restricted food intakes show similar weight changes. Increases in water consumption usually, but not invariably, accompany the weight gain. The loss of weight after progesterone withdrawal or at the end of pseudopregnancy is accompanied by a reduction in food and water consumed as after parturition or pseudo‐parturition.

Analyses of the weight gain in progesterone‐treated mice with increased food intakes revealed retention of water, fat and protein, together with an increased total energy expenditure of about 10 per cent. Retention of water and protein and increased energy expenditure still occurred with the food intake restricted to sub maintenance levels, i. e. even in the presence of continuous losses of body fat.

It is concluded that progesterone fundamentally affects body weight by promoting water and nitrogen retention and, at the same time, increasing energy expenditure. The increase in food intake usually observed is, at least in part, a secondary response to the demands created by the latter two effects and fat deposition occurs also if this response is overadjusted.
THE EFFECT OF BLOOD PRESSURE UPON CHEMORECEPTOR DISCHARGE TO HYPOXIA, AND THE MODIFICATION OF THIS EFFECT BY THE SYMPATHETIC‐ADRENAL SYSTEM
Authors: Lee K. D. , Mayou R. A. , Torrance R. W.
Published: December 2014

The discharge in single‐ or few‐fibre chemoreceptor preparations from the aortic nerve of the cat has been measured, and plotted against the prevailing blood pressure. If the blood pressure is raised mechanically, the relation between these two variables differs from that found when the pressure is raised reflexly or by catechol amines. It is suggested that the sympathetic‐adrenal system may have a significant effect on the sensitivity of chemoreceptors.
THE ACCURACY OF THE INDICATOR ABSORPTION METHOD OF MEASURING MAMMARY BLOOD FLOW BY THE FICK PRINCIPLE
Authors: Rasmussen F. , Linzell J. L.
Published: December 2014

The distribution and fate of antipyrine after injection into the teat of goats has been determined and the blood flow, calculated on the Fick principle from uptake from the tissue, compared with the blood flow measured by other methods. In both conscious and anæsthetized animals and in perfused glands the antipyrine absorption method was usually accurate but occasionally overestimated the flow. The reasons for this and the limitations of the method are discussed.
FŒTAL AND NEONATAL HÆMOGLOBINS IN SHEEP AND GOATS
Authors: Breathnach Caoimhghin S.
Published: December 2014

Differences in alkaline denaturation rate, electrophoretic mobility and ease of elution from fixed red cells have been used to study the fœtal and adult hæmoglobins in faetal and newborn lambs and kids. Fœtal hæmoglobin was found exclusively before and at birth in both species. Adult hæmoglobin appeared in the first week, amounted to half the total by the third week and had completely replaced the fœtal pigment at the end of two months. The anomalous failure of agreement between the percentages measured by denaturation rate and differential elution are in large measure accounted for by the greater size of the fœtal erythrocytes.
THE NEPHROPATHY OF EXPERIMENTAL MAGNESIUM DEFICIENCY: AN ELECTRON MICROSCOPIC STUDY
Authors: Sabour M. S. , Hanna Samir , MacDonald Mary K.
Published: December 2014

Thirty rats were divided into three equal groups; the control group C and the two experimental groups were fed on diets identical in all respects other than the magnesium content. Group A were kept on a magnesium deficient diet for 13 days, and group B for 3 days. At the end of the experimental period, muscle, kidney and plasma were analyzed for their Mg and Ca contents and the kidneys were examined by the light and electron microscopes.

No significant change was noted in the magnesium content of the kidneys of the deficient rats. In skeletal muscles, there was progressive depletion of magnesium, and the plasma magnesium also fell. The only highly significant result in the calcium content was a marked increase in the kidneys of the deficient groups.

After as early as 3 days on the deficient diet, foci of dilated proximal tubules were seen in the cortico‐medullary zone even by the light microscope, but after 13 days they were observed all over the cortex and outer zone of the medulla. The lining cells of the slightly dilated tubules were swollen and vacuolated. As the dilatation increased, the tubular lining cells appeared to lose their brush border and to become flattened. The cells contained structureless cytoplasmic granules. Important negative findings are the normal appearance of the mitochondria, the normal thickness of the basement membrane, and the absence of any demonstrable obstruction in the dilated tubules or in more distal sites.

It seems possible that in magnesium deficiency the proximal tubule cells, which normally reabsorb Ca++ and Mg++ by a common transport mechanism, reabsorb an excess of Ca++ from the glomerular filtrate which is deficient in Mg++. The excess of absorbed calcium ions is largely deposited locally in these cells, appearing as the dense granules. This would explain the high calcium content in the kidneys and the nephrocalcinosis in late stages.
SIGNIFICANCE OF CHANGES IN HEXOSAMINE AND IN NITROGEN IN THE DIGESTA OF THE ALIMENTARY TRACT OF THE SHEEP
Authors: Badawy A. M. , Cuthbertson D. P.
Published: December 2014

Previous work had shown that the method of killing an animal affected the integrity of the mucosa of its digestive tract and as a consequence the content of nitrogen in the digesta.

In the contents of the abomasum and the small intestine (divided into 4 equal lengths) of a group of sheep shot and bled and in another group anæsthetized and bled it was found that total nitrogen and hexosamine concentrations in the dry matter of the digesta or in relation to the dietary lignin as a marker rose considerably from the abomasum to the first quarter of the small intestine. The increase in hexosamine was less than that of total nitrogen. After the first quarter of the small intestine a decrease in total nitrogen was observed distally, but the proportion of hexosamine increased. In a third group of sheep from which the contents were obtained under anæsthesia alone the increments, both of total nitrogen and hexosamine, were less. In conscious sheep on the same kind of diet and fitted with cannulas, similar but smaller changes were found.

Mucoprotein is probably the main source of hexosamine in the proximal zone of the small intestine but distally microbial cell wall polysaccharides containing glucosamine become a considerable source.

The condition of the animal at the time of sampling greatly affects the significance to be attached to the nitrogenous constituents of the digesta.
THE PERMEABILITY OF THE BLOOD CAPILLARIES OF THE LEG TO THE LIPOPROTEINS IN VARIOUS HYPERLIPAEMIC STATES IN THE RABBIT
Authors: Courtice F. C. , Munoz-Marcus M. , Garlick D. G.
Published: December 2014

The transference of lipoproteins across the walls of blood capillaries was determined by measuring the concentration of their components in plasma and in lymph collected from the leg, both before and after injuring the paw by heat. These measurements were made in groups of normal rabbits in which the lipid levels were increased by Triton WR‐1339, cortisone, alloxan or hæmorrhage, and in cholesterol‐fed animals given either Triton or cortisone.

The transference of the lipoproteins in all these different hyperlipaemic conditions was considerably increased by injury, and, both before and after injury, varied inverselv with the size of the macromolecules concerned.

The results showed that one way in which Triton, cortisone and alloxan might inhibit atherosclerosis in the cholesterol‐fed rabbit was by changing the lipoprotein pattern, decreasing the amount at the lower end and greatly increasing the amount at the upper end of the spectrum in relation to size and Sf values, thereby decreasing the amount of lipoprotein filtered through the vascular endothelium.

The composition and stability of lipid in the lymph and, therefore, in the tissue fluid, also varied considerably in the different conditions studied and these factors were also probably important in determining whether or not lipid was deposited in an atherosclerotic lesion.

The experiments support the view that small, cholesterol‐rich lipoproteins are the most likely to be deposited in the intima because they are more readily transferred across the endothelium, are rich in cholesterol, which cannot be broken down, and are probably less stable than the lipoproteins in conditions of hypertriglyceridæmia.
VISUAL FIELD PROJECTION ON THE DORSAL NUCLEUS OF THE LATERAL GENICULATE BODY IN THE RABBIT
Authors: Choudhury B. P. , Whtteridge D.
Published: December 2014

On the surface of the dorsal nucleus of the lateral geniculate body the projection of the visual streak is more magnified than the rest of the retina and is orientated approximately mediolaterally with the nasal visual field projected medially. In the projection of the visual streak the nasal field has a larger representation on the surface and a much larger representation in the depth of the nucleus than the temporal field.

On the posteromedial segment of the surface of the nucleus a secondary area is observed, where the lower nasal field is reduplicated. The binocular field is located in the depth of the nucleus on its medial side.
THE EFFECT OF PAPILLARY MUSCLE DAMAGE ON ATRIOVENTRICULAR VALVE FUNCTION IN THE LEFT HEART
Authors: Hider C. F. , Taylor D. E. M. , Wade J. D.
Published: December 2014

The effects on competence of the mitral valve and the rate of development of isometric tension within the left ventricle have been studied by comparing dogs in which a papillary muscle was inactivated by ethanol injection with control dogs in which a similar injection was made into the lateral wall of the left ventricle. Immediately after the alcohol injection into papillary muscle three dogs out of eleven developed mitral incompetence. This does not appear consistent with the theory that papillary muscle contraction is essential for valve competence during ventricular contraction. Three months after the injection nine dogs survived in each group. Mitral valve dysfunction was present in five experimental, but in only one control dog and there was a trend to less efficient isometric contraction of the left ventricle in the experimental group. Possible reasons for these findings are discussed and a predominant rôle for the papillary muscles during the isometric rather than the ejection phase of ventricular systole supported.
ALDOSTERONE AND THE METABOLISM OF MAGNESIUM AND OTHER MINERALS IN THE SHEEP
Authors: Scott D. , Dobson A.
Published: December 2014

D‐aldosterone was infused into sheep at a rate similar to that at which it is secreted by the adrenal gland during acute sodium deprivation. The infusion produced a consistent fall in magnesium concentration in the plasma which could not be attributed solely to hæmodilution. This hypomagnesæmia was not exacerbated by an increased intake of potassium. Aldosterone infusion produced many of the changes in mineral levels in the plasma associated with primary aldosteronism in the human. Changes produced in the amount of magnesium appearing in the urine by intramuscular injection of aldosterone were due to the injection procedure rather than to the aldosterone. Neither intramuscular injection of aldosterone nor acute sodium depletion produced hypomagnesæmia.
ANTIDIURETIC HORMONE ACTIVITY IN SHEEP AFTER FEEDING
Authors: Stacy B. D. , Brook A. H.
Published: December 2014

Pen‐fed sheep increased the concentration of their urine after receiving their daily ration, and evidence is presented to indicate that the change was brought about by the action of antidiuretic hormone (ADH). Post‐prandial urine, but not urine from unfed animals, caused inhibition of urine flow when injected into water‐loaded sheep. The antidiuretic material in post‐prandial urine was assumed to be ADH because (a) it could be extracted by a specific procedure, (b) it was similar to synthetic arginine vasopressin in its action on water and electrolyte excretion in water‐loaded sheep, and (c) its biological activity was destroyed by thioglycollate or by trypsin. It was also found that there was an increase in plasma osmotic pressure after feeding, so that conditions favoured the release of ADH. It is therefore concluded that normal, pen‐fed sheep regularly experience conditions that classically stimulate the neurohypophysis to control the renal excretion of water by secreting ADH. The action of ADH on electrolytes is discussed, and it is concluded that the sheep, like other animals, does not depend upon the hormone to regulate the renal excretion of Na and K.
A METHOD FOR INDEPENDENT AND REVERSIBLE EXCLUSION OF CHANGES IN ACTIVITY OF THE CAROTID CHEMORECEPTORS AND BARORECEPTORS: STUDIES ON SYSTEMIC HYPOXIA
Authors: de Burgh Daly M. , Scott Mary J.
Published: December 2014

A method is described whereby, in the anæsthetized dog, changes in the activity of the carotid body chemoreceptors and carotid sinus baroreceptors can be independently and reversibly excluded. The carotid sinuses and bodies are isolated from the circulation and perfused at constant volume flow with arterial blood from the same animal. The perfusion pressure is controlled by means of a Starling type of resistance, the air‐space of which is connected to an artery so that the carotid sinus pressure is automatically maintained at the same level as the systemic blood pressure. Changes in carotid body chemoreceptor activity are excluded by perfusing the carotid bifurcation regions with arterial blood from a donor dog, the baroreceptors remaining functionally normal. Changes in activity of the carotid baroreceptors are excluded by maintaining constant the pressure in the air‐space of the Starling resistance, and therefore in the carotid sinuses; the carotid bodies are perfused with recipient dog's blood and remain functionally normal. Evidence is presented that in the vagotomized dog, reflexes from both the carotid chemoreceptors and baroreceptors contribute to the maintenance of the arterial blood pressure in acute systemic hypoxia produced by inhalation of 7–12 per cent O2 in N2. It is concluded that caution is necessary when interpreting the results of experiments based on observations made before and after interruption of the passage of nerve impulses in the carotid sinus or aortic nerves which contain afferent fibres to both types of receptor.
COMPOSITION OF THE RENAL CORTEX AND MEDULLA OF RATS DURING WATER DIURESIS AND ANTIDIURESIS
Authors: Saikia T. C.
Published: December 2014

The composition of the renal papilla, medulla and cortex was studied in rats during hydropenia and water diuresis, and a few observations were made on hamsters.

In confirmation of earlier findings, osmolality increased progressively from the outer medulla towards the tip of the papilla in hydropenia; this osmolal gradient was due largely to increasing concentration and content of sodium and urea. The osmolality at the tip was close to that of simultaneously collected urine. In water diuresis, this osmolal gradient was smaller but still present.

Ammonium content and concentration increased progressively from the outer medulla towards the papilla.

In water diuresis, the concentration and content of urea fell, but the gradient was still present. Sodium was little altered, and the fall in ammonium content, though considerable, contributed little to the total osmolal change.

Potassium concentration and content were high in the terminal segment in diuresis and antidiuresis, and in water diuresis exceeded the hydropenic value.

The water content increased progressively from the outer towards the inner medulla, but at the tip it was lower than in the adjacent segment. This distribution was qualitatively similar in both conditions, but the absolute level was higher in all medullary segments in water diuresis.

The results are discussed in relation to the mechanism of production and maintenance of medullary hypertonicity.
THE ACUTE EFFECT OF VASOPRESSIN UPON THE COMPOSITION OF THE RAT RENAL CORTEX AND MEDULLA
Authors: Saikia T. C.
Published: December 2014

Rats in water diuresis were given intravenous injections of vasopressin, or of isotonic NaCl for controls. Serial urine sampling showed that maximal osmolality and minimal flow were achieved half an hour after vasopressin injection, and that urea excretion was low at this time. In animals killed half an hour after injection, the composition of the renal papilla, medulla and cortex was studied.

The urea and ammonium concentration and content increased in the inner medulla after vasopressin injection, and the water content increased in all the kidney slices, but significantly so only in the papilla. The medullary osmolality did not alter appreciably, the accumulation of urea and ammonium being counter‐balanced by the increase of water. The urine osmolality did not reach the level found in the medulla. No appreciable change of sodium or potassium concentration or content of kidney slices was observed after vasopressin injection. The results are discussed in relation to means whereby vasopressin induces antidiuresis and urinary hypertonicity.
THE FUNCTION OF THE CALLOSAL CONNECTIONS OF THE VISUAL CORTEX
Authors: Choudhury B. P. , Whitteridge D. , Wilson M. E.
Published: December 2014

There is anatomical evidence in cats and baboons of cells at the margin of area 17 which have callosal connections to corresponding points in the opposite hemisphere. The function of such a pathway has been studied in cats after one optic tract has been cut. The corresponding hemisphere now gives early visual responses only at the margin of area 17. Such responses can only be elicited by light stimuli near the vertical meridian of the visual field. These responses are abolished by cooling the corresponding points in the opposite hemisphere and by cutting the corpus callosum. This pathway appears to provide some functional union for the two halves of the visual field.
FLUID AND SOLUTE TRANSPORT ACROSS RAT COLONIC MUCOSA
Authors: Parsons D. S. , Paterson C. R.
Published: December 2014

A method is described of preparing everted sacs of rat colonic mucosa free of the smooth muscle layers. Fluid movement across the wall of the sacs may be maintained for periods of up to 4 hr. in vitro under aerobic conditions in the presence of a substrate. Glucose, mannose, acetate, butyrate and to a lesser extent, pyruvate, are effective substrates. Although taken up from the mucosal fluid, glucose is most effective as a substrate for fluid movement when present in the transmucosal fluid. In the presence of glucose, the rate of lactate formation is low under aerobic conditions in vitro, but increases some eight‐fold under anaerobic conditions. With glucose present, lactate appears at a higher concentration in the transmucosal fluid than in the mucosal fluid. The colon can transport water from mucosal fluid into the transmucosal fluid against an osmotic gradient; reasons are given for supposing that this fluid movement is secondary to the functioning of an active solute transport mechanism. Glucose, galactose and 3‐0‐methylglucose are not subjected to active transport (translocation) across the colonic mucosal layers against a concentration gradient.
THE BEHAVIOUR OF PLATELETS IN VIVO
Authors: Silver M. D. , Stehbens W. E.
Published: December 2014

Observations have been made on platelet behaviour in non‐inflamed and growing blood vessels in the rabbit ear chamber. Platelets showed little tendency to aggregate or to adhere to endothelium. Most commonly a few adhered to leucocytes which were attached to or rolled along the endothelium.

Platelets adhered to leucocytes in larger numbers and aggregated to form microthrombi and emboli following mild trauma and intravascular injection of adenosine diphosphate, Pelikan ink and methyl cellulose. Following intravascular administration of thrombin and bacterial lipopolysaccharides (S. typhosa and E. coli) platelet aggregation was observed and later hyaline thrombi. In addition, aggregation of erythrocytes occurred with methyl cellulose.
THE GOLGI APPARATUS IN SMALL LYMPHOCYTES AND IN TRANSFORMED BLAST CELLS
Authors: Coulson A. S.
Published: December 2014

The Golgi apparatus can be demonstrated by incubating cells in a medium containing lead nitrate and either thiamine pyrophosphate or a nucleoside diphosphate. Enzyme activity at the Golgi membranes hydrolyses the thiamine pyrophosphate or nucleoside diphosphate and a precipitate of lead phosphate is formed. By converting this precipitate into lead sulphide the Golgi apparatus can be visualized microscopically.

The enzyme activity in freshly separated human small lymphocytes is barely detectable.

After tissue culture for 80‐90 hr. with an antigenic stimulus some of the small lymphocytes transform into blast cells. The transformed blast cells contain a well‐developed Golgi apparatus which is basically a figure‐of‐eight shape. Blast cells in mitosis do not contain a Golgi apparatus.

This evidence suggests that the transformed blast cell is manufacturing protein, possibly antibody.