bluuebunny/crossref_metadata_2025_split huggingface dataset:
Localization of Alkaline Phosphatase in Mammalian Bones
Authors: Lorch I. Joan 
Published: April 2021

ABSTRACT
1. Adult mammalian bones may be decalcified in sodium citrate-HCl buffer at pH 4-5. The addition of Zn (10-4 M) prevents irreversible destruction of alkaline phosphatase which is, however, partially inactivated.
2. The phosphatase is subsequently reactivated by placing the tissues in 1 per cent, sodium barbitone +0·075 per cent, glycine at 37°C. for 2-3 hours.
3. In this way thin paraffin sections free from preformed phosphate are obtained.
4. Phosphatase is demonstrated by the Gomori-Takamatsu (1939) technique.
5. Long bones, ribs, and membrane bone from the skull of adult rats and mice and of new-born kittens were examined.
6. Phosphatase was found to be present in the endosteum, the inner layer of the periosteum, the Haversian canals and linings of vascular and marrow spaces, the nuclei of bone marrow and connective tissue-cells, and in isolated osteocytes. The hypertrophic cartilage was positive in both nuclei and matrix in the rodent bones but negative in the kitten bones. The bone matrix and the small-celled cartilage were negative throughout.
7. The possible significance of these findings in relation to the function of alkaline phosphatase is discussed.
Studies upon the Gram Reaction of the Basiphil Cells of the Anterior Pituitary Part II. Observations upon the Effects of Various Methods of Fixation
Authors: Wilson R. R. , Foster C. L. 
Published: April 2021

ABSTRACT
To investigate the effects of fixation on the Gram reaction in the pituitary basiphil granules, frozen sections were made from fixed and unfixed glands, paraffin sections from frozen-dried glands, and paraffin sections in the usual way from whole glands, as well as from several pieces of glands embedded in one block. The fixatives were various well-known mixtures and single substances. Staphylococci were also studied, after treatment with some of the fixatives.
The basiphil granules were always Gram-positive after fixation in formaldehydesaline, formaldehyde-Zenker, Zenker’s fluid, and Zenker stock-solution. Frozen sections of unfixed glands, and sections of frozen-dried glands, were always Gramnegative ; but such sections were usually Gram-positive if left in formaldehyde-saline for at least 12 hours before staining. All other fixatives studied gave negative results. The staphylococci were always Gram-positive.
These findings, and some questions arising from them, are briefly discussed.
The Stomatogastric Nervous System of Arenicola
Authors: Whitear Mary 
Published: April 2021

ABSTRACT
The stomatogastric system of Arenicola marina L. is in the form of a plexus of nerve-bundles connecting the supra-oesophageal ganglia and the circum-oesophageal commissures with a ring ganglion situated in the gut wall at the anterior limit of the oesophagus; the plexus continues down the length of the oesophagus. Numerous sense cells occur in the epithelium of the proboscis and oesophagus. The anatomy of the stomatogastric system is essentially the same in A. ecaudata Johnston and in A. claparedii Levinsen.
Nuclear Transplantation in Amoebae. I. Some species characters of Amoeba proteus and Amoeba discoïdes
Authors: Lorch I. Joan , Danielli J. F. 
Published: April 2021

ABSTRACT
1. The object of this work was to find characteristic differences between stock cultures of A. proteus and A. discoides in order to assess results obtained in experiments involving nuclear transplantation.
2. Previous work on the two species was not found to yield satisfactory diagnostic features.
3. Methods of establishing and maintaining clones and of observing living amoebae are described.
4. As a result of the study of outline drawings of active amoebae and of measurements of the largest diameter of the nuclei, two characters were found which enabled us to distinguish cultures of A. proteus and A. discoides. They were (a) the pattern of locomotion and (b) the distribution of nuclear diameters within a culture.
5. The outlines of active A. discoides tend to be more serrated than those of A. proteus. Outline drawings were readily sorted by independent observers into two categories corresponding fairly closely to the two species. By this method healthy cultures can be identified. Individual amoebae are not always identifiable.
6. An analysis of the longest nuclear diameters of amoebae of the two species showed that the average of a clone and the distribution of nuclear diameters within a clone are typical for each species and are little affected by the age and state of nutrition of the culture. The average nuclear diameter in our cultures, which was found to be independent of the nuclear size of the parent amoeba, was 45 p (s. d. 5-6) for A. proteus and 38-2 p (s.d. 3-6) for A. discoides.
7. The possibility is discussed of using physiological and serological, rather than morphological properties to distinguish between the species.
The Orientation of the Optic Axis of Spicules of Leucosolenia complicata
Authors: Jones Walter Clifford 
Published: April 2021

ABSTRACT
The orientation of the optic axes of the spicules of Leucosolenia complicata has been studied by using isolated spicules and longitudinal sections of the oscular tubes. For tri- and quadri-radiates the mean angle of inclination of the optic axis to the tube wall varies with the distance of the spicule from the oscular edge, particularly over the first 200 μ The spicule form likewise varies with position, but is not closely correlated with the orientation of the optic axis : two spicules can have the same optic angle but different shapes, or the same shape and yet different optic angles. For curved monaxons the optic axis is directed almost at right angles to the spicule axis at the distal end, and the spicule curvature is independent of the position in the tube. Slender monaxons, on the other hand, have an optic axis coincident with the spicule length. It seems a general rule, at least for spicules of L. complicata and L. coriacea, that the optic axis of the first formed calcite rudiment lies in the direction of the cell division (or cell association) that directly precedes spicule formation.
A mechanism is suggested for the orientation of the optic axis. This is explained in terms of an oriented overgrowth of the calcite upon an organic precursor, which is structurally fixed and oriented within the formative cell complex. The arrangement of this complex, by mechanical factors arising during the development of the oscular tube, results in the orientation of the optic axis of the developing spicule. The hypothesis is in accordance with the observations of Minchin on spicule formation.
Note on the Histochemical Localization of Glycogen and Pentosepolynucleotides in the Visual Cells of the Chick (Gallus gallus)
Authors: Rabinovitch M. , Mota Ivan , Yoneda S. 
Published: April 2021

ABSTRACT
Glycogen was studied in retinas of the chick (Gallus gallus), fixed in Gendre’s fluid and stained by the periodic acid/Schiff method. In agreement with some of the earlier data on the subject, obtained with less suitable methods, glycogen was found in the paraboloid of accessory cones and in the characteristically shaped paraboloid of the rods. Basiphilia, observable by means of the gallocyanin-chromalum stain and removable by ribonuclease or perchloric acid, was found in the inner segment of both chief and accessory cones, with the exception of the ellipsoid region.
A Study of the Embryonic development of the Gooseberry Sawfly, Pteronidea ribesii
Authors: Shafiq Saiyid Ahmad 
Published: April 2021

ABSTRACT
The following points in the descriptive embryology of the sawfly appear to be important especially for comparison with the higher Hymenoptera, e.g. the honey bee.
The earlier stages of development (formation of the blastoderm, germinal layers, &c.) take relatively more time in the honey bee than in the sawfly, while the later stages of development (organogenesis) take more time in the sawfly. Only two well-defined germ layers are formed—the outer (ectoderm) and the inner (mesoderm). Cells proliferate from the mid-ventral area of the germ band and spread out to form the inner layer in the sawfly, whereas in the honey bee it forms as a middle plate. Localized proliferations at the anterior and the posterior end of the germ band form two cell-clumps; from these differentiate the midgut epithelium, mesoderm of the procephalic region of the head, muscle layer of the proctodaeum and stomodaeum, and also the germ cells. These are here called the mesendoderm rudiments. The coelom sacs are not well defined from each other but form a more or less continuous tube as in the honey bee. Nucleoli appear in the cells and the cytoplasm becomes basiphil immediately after the formation of the inner layer. Changes in the basiphilia of cells during development are described. The proctodaeum first appears as an invagination in the upturned (dorsal) part of the germ band, which is all used up in its formation, and the edges of the ventral germ band rise up to complete the dorsal closure. The Malpighian tubules develop from the blind end of the proctodaeum and are regarded here as ectodermal; in the honey bee they develop before the proctodaeum is formed. In the advanced embryo the midgut cells have big vacuoles in them and throw out pseudopodia into the lumen of the gut, and the cells of the salivary gland acquire large lobed nuclei. Agreement is expressed with Snodgrass’s view (1938) that the head is composed of four segments and a procephalic region. The labrum has a paired origin (in the honey bee it is unpaired in origin); and as in the honey bee the premandibular segment is not developed. The rest of the body is composed of three thoracic and ten abdominal segments. Paired appendages appear on the thoracic and the second to seventh and tenth abdominal segments (in the honey bee abdominal appendages are not formed). The germ cells arise from the posterior mesendodermal rudiment. In the honey bee they appear to be derived from the genital ridges. There are no blastokinetic movements as in the honey bee. The serosa persists till the hatching of the embryo and secretes a cuticle at an early age. The amnion is not well developed and is transitory; in the honey bee only one embryonic envelope forms.
A Histochemical Study of Fat Absorption in the Small Intestine of the Rat
Authors: Hewitt W. 
Published: April 2021

ABSTRACT
Experiments are described in which sections from the small intestine of rats, fed on triolein hours previously, were examined with Sudan black and the acid haematein test, with and without Sudan red coloration.
The histochemical appearances in the epithelial cells of the mucous membrane are described. Lipoid can be observed not only within the epithelial cells and their free border but also as particles between the cells.
Properties of the Minerals in the Exuvia of Crustacea
Authors: Needham A. E. 
Published: April 2021

ABSTRACT
An unusual reaction between material in the exuviae of Crustacea and pure cold mercuric chloride, resulting in the deposition of a bright red compound, led to the discovery that, contrary to expectation, the inner surface of the fresh moult, and even of the inter-moult exoskeleton, is strongly alkaline (pH = 9·1). This is near the optimum for both alkaline phosphatase and carbonic anhydratase, which both may be active in resorption of mineral preparatory to ecdysis. Correlations between the distributions of the red Hg-compound, phosphate, carbonate, alkaline phosphatase, and pigmentary pattern have been found in various Crustacea. The reaction with cold HgCl2 is given also by the millipede exoskeleton, the molluscan shell, the calciferous gland-material of earthworms (pH 9·2–9·4) and by calcareous sponges, but not by echinoderm or vertebrate skeletons, and not by the exoskeleton of insects, spiders, and centipedes, which lack mineral. The compound(s) with mercuric chloride are probably chiefly oxychlorides. A steady, if slight, solution of the skeletal carbonate and phosphate is necessary to maintain the observed high pH, and to permit the formation of these mercury-compounds.
An Investigation of the Innervation of the Thymus Gland of the Common Mouse, Mus musculus
Authors: Rankin J. J. 
Published: April 2021

ABSTRACT
The anatomical relations of the thymus gland in mice have been studied in serial sections throughout the entire thoracic and posterior cervical regions. No evidence was obtained that the thymus has a secretory function under the control of the nervous system, and no nerve fibres or endings were observed in the proximity of the thymocytes, Hassall’s corpuscles, or reticular cells. The thymic innervation resembles that of the lymph nodes rather than that of the adrenal gland or of the spleen and the neuro-histological picture was unchanged during accidental or age involutions. The thymic innervation consists entirely of autonomic vasomotor nerves originating in an outlying sympathetic plexus—the ‘thymic plexus’, and it is suggested that thymus functions are controlled by vasodilatator and vasoconstrictor mechanisms with the possible aid of thymotropic hormones carried in by the blood-stream. The thymus may aid in the regulation of the lymphocyte content of the blood, acting as a lymphocytic reservoir instead of as a lymphocytopoietic organ.
The source of thymic innervation could not be determined solely by anatomical methods and the majority of current histological techniques were found to be unsuitable for differentiating between nervous and non-nervous argyrophilic fibres. The basic techniques of Holmes and Romanes appeared to satisfy the necessary criteria and Steedman’s ester wax method was successfully used in conjunction with these techniques.
The Structure of the Corpus Cardiacum of Locusta migratoria
Authors: Nayar K. K. 
Published: April 2021

ABSTRACT
The corpus cardiacum of Locusta consists of a syncytium containing nuclei of two sizes. The most obvious cytoplasmic inclusions are spheroid bodies, mostly about 0·6 μ in diameter, which are easily seen in the living tissue, especially by phase-contrast microscopy. They do not appear in routine microscopical preparations, but are blackened by the classical ‘Golgi’ techniques. They give positive reactions for phos- pholipines. The cytoplasm also contains very numerous minute granules, which appear to be mitochondria.
A General-Purpose Method of Silver Staining
Authors: Peters A. 
Published: April 2021

ABSTRACT
A method of silver staining for paraffin sections has been described. Sections should be fixed in either Nonidez fixative, 4% formaldehyde, or 4% formaldehyde saturated with mercuric chloride. The sections are impregnated for 16 hours in 1/20,000 silver nitrate at pH 8 or 9 and developed in a glycine physical developer after the reducible silver has been removed with a 2% solution of sodium sulphite.
The effect of pH on impregnation has been described. A spectrum of staining was obtained in which nerve fibres began to stain appreciably at pH 7, cell nuclei at pH 8, cell cytoplasm at pH 9, and connective tissue at higher pH values. Therefore, impregnation should be carried out at pH 8 to obtain a good staining of nerve fibres and at pH 9 if some staining of cell bodies is also required.
Studies of the impregnation of nervous tissue elements: II. the nature of the compounds responsible for the impregnation of axons; practical considerations
Authors: Wolman M. 
Published: April 2021

ABSTRACT
Axoplasm and axolemma differ in their chemical and physical characteristics. The impregnation of axons is mainly due to a compound which is soluble in hot organic solvents and which appears to be situated in the axoplasm.
Ethylenic linkages and hydroxyl groups play no role in the impregnation of axons. Sulphydryl and carbonyl groups appear to be partly responsible. These groups are situated mainly in the axoplasm, although sulphydryls are present also in the axolemma. The impregnation of axolemma depends to a great extent on chemical groups which could not be identified.
The fact that solutions of Ag diammine are more suitable for impregnating axons than those of AgNO3 might be due to one of the following factors : (1) that the reducing groups of the axons are more easily oxidized at high pH levels; (a) that the complex diammine ion might exert a higher oxidizing activity when reacting with some tissue molecules; (3) that the rate of reaction of the reducing groups of the tissue with the Ag diammine ion might be faster than that with the silver ion.
The Bielschowsky procedure may be carried out successfully on sections of tissue embedded either in paraffin wax or carbowax. With the former procedure care should be taken to minimize contact with mixtures of hot solvents. A further intensification of impregnation of paraffin sections is obtained by treating sections for 24 hours in 4% formaldehyde prior to the Bielschowsky procedure.
An easily made tissue culture perfusion chamber
Authors: Dick D. A. T. 
Published: April 2021

ABSTRACT
A perfusion chamber is described with which a tissue culture can be irrigated successively with different immersion media. Only 1–2 ml. of medium are required for each change, which can be accomplished within 1 minute. Simplicity of design permits speed and economy in manufacture. Perfusion by suction instead of by positive pressure has eliminated certain drawbacks of previous designs. Mixing effects in the chamber have been studied. Any component of an immersion medium can be reduced to 0·5% of its initial concentration by the use of only 2 c.c. of fresh medium. The chamber has been used in the techniques of immersion refractometry and interferometry of living cells.
Amoeba taylorae n.sp.
Authors: Hayes Catherine 
Published: April 2021

ABSTRACT
In material collected from Tannoch Loch, Dunbartonshire, a large free-living, hitherto undescribed amoeba was found. Individual specimens vary in length from 420 to 500μ and in width from 70 to 140μ. Viewed over a black background this amoeba looks dense, white, and opaque, while in transmitted light it has a dusky, almost black, hue, due to the presence in the endoplasm of a large number of small crystals uniform in size, slender and pointed at both ends. There is always a uroid at the hinder end surrounded by bits of debris. The one large nucleus is without a karyosome but has masses of chromatin scattered through the nuclear substance. As a rule there is only one large contractile vacuole, but occasionally a few small ones may be seen at the hinder end. A certain number of nutritive spheres are always present. The author considers this amoeba to be a new species and names it Amoeba taylorae.
The Distribution of Hatching within the Cyst of the Potato Root Eelworm, Heterodera rostochiensis
Authors: Onions T. G. 
Published: April 2021

ABSTRACT
A serial-sectioning technique is described for cysts of the potato root eelworm. The distribution of hatching among eggs contained in the cysts is investigated by this technique. It is shown that there are significant differences in the numbers of larvae emerging from different parts of the cyst, i.e. hatching is not random. There is a tendency for eggs near the cyst wall to hatch sooner than eggs nearer the centre of the egg mass. The position of eggs in relation to the natural openings of the cyst, at the neck and vulva, is apparently without influence on the distribution of hatching. Although the cyst wall is permeable to the hatching stimulant it is argued that the hatching pattern is more likely to be due to a gradient of oxygen tension within the cyst.
The Posterior Lobes of the Brain of Nephtys and the Mucus-Glands of the Prostomium
Authors: Clark R. B. 
Published: April 2021

ABSTRACT
A pair of lobes is attached to the posterior margin of the supra-oesophageal ganglion of some species of Nephtys. They are filled with large, vacuolated mucus-cells similar in appearance and histochemical properties to those found in the anterior part of the prostomium, in the lateral walls of it, and in the parapodia. The mucus-cells of the posterior lobes, and sometimes those of the anterior prostomial group also, have long necks which run in a tract to the epidermis, where they open to the exterior. When this is so, they replace the epidermal mucus-cells found in the lateral walls of the prostomium in species lacking posterior lobes. It is suggested that there has been a centripetal migration of epidermal mucus-cells into the posterior lobes and to the anterior prostomial group, a phenomenon closely paralleling that found in the evolution of the nermertean cerebral organ. In one species, Nephtys cirrosa, the posterior lobe cells appear to have undergone a further modification, for they are much more closely integrated with the nervous system and differ in appearance from those of other species, coming to look, at least superficially, like the majority of neurosecretory cells in the brain.
Histochemical Methods for Protein-bound Sulphydryl and Disulphide Groups
Authors: Gomori G. 
Published: April 2021

ABSTRACT
Histochemical methods for the localization of protein-bound sulphydryl groups were compared in a critical fashion. As far as localization is concerned, several of the methods published were found to be satisfactory. However, from the point of view of approximate visual quantitation, the results are confusing. The two best methods for the histochemical detection of protein-bound sulphydryl groups are the tetrazolium method and Barrnett and Seligman’s dihydroxydinaphthyldisulphide technique.
The Haemocytes and Connective Tissue Formation in an Insect, Rhodnius prolixus (Hemiptera)
Authors: Wigglesworth V. B. 
Published: April 2021

ABSTRACT
The amoebocytes, which form the most abundant type of blood-cell in Rhodnius, contain rounded, oval, or rod-shaped inclusions which stain by the periodic acid /Schiff method. These are believed to be neutral mucopolysaccharides. The amoebocytes apply themselves to the basal membranes, which likewise are PAS-positive, and appear to contribute to these membranes by discharging their contents. They insinuate themselves into the developing muscles and give rise to the sheaths of connective tissue by which the muscle fibres are surrounded. And they collect around deposits of injected Indian ink, producing similar sheets of PAS-positive material, presumably mucopolysaccharide.
The chitinous endocuticle is PAS-negative (except in a few special regions such as the neck and the conjunctival membranes of the limbs). It becomes positive during digestion by the moulting fluid. The tracheae react similarly.
Other PAS-positive structures which are not produced by the amoebocytes are the striated border of the mid-gut, the basement membrane of the gut, the perilemma around the ganglia and nerves, and the ground substance within the ganglia.
The Histochemical Localization of β-Glucuronidase in the Liver of the Newt
Authors: Billett F. , McGee-Russell S. M. 
Published: April 2021

ABSTRACT
The localization of β;-glucuronidase in the newt liver, by the use of quinolyl-8-glu-curonide as a substrate, is described. The technique previously used for the digestive gland of the Roman snail may be applied successfully to the newt tissue. Results suggest, however, that the treatments involved produce considerable destruction of the fine structure of the cytoplasm, and that present techniques based upon the precipitation of the ferric salt of 8-hydroxyquinoline cannot give a fine intracellular localization of the enzyme.
A Demonstration of Dehydrogenase Activity in the Mitochondria of Living Cells
Authors: Hughes Arthur 
Published: April 2021

ABSTRACT
A method is described whereby fresh specimens of neural tissues are examined in squashes under the phase microscope. When squashed in contact with the sensitive tetrazolium derivative known as ‘INT’, granules of formazan are precipitated around the mitochondria within the neurocytoplasm. Application of these techniques to squashes of the spinal cord of the ray has given a direct demonstration of the dehydrogenase activity of mitochondria within fibres of the white matter of the cord.