Ultraviolet Fluorescence Microscopy Research Articles

Polymorphic Variation in the Structure of Aerial Sclerotia of Coprinus cinereus

Aerial sclerotia of different wild-type strains of Coprinus cinereus differed in their internal structure. The more common of the two polymorphic forms (called the Z-type) had a rind which was only one cell thick; the other form (the H-type) had a rind many cells thick which extended to at least half the diameter of the sclerotium. Visible light microscopy, ultraviolet fluorescence microscopy and scanning electron microscopy were used to characterize the sclerotia formed by a range of dikaryotic mycelia to establish the genetic relationships between the polymorphic structures. The Z-type is the wild-type and genetically dominant form. The H-type is a naturally occurring variant caused by an allele of the gene scl-1 which we designate scl-1 H. The scl-1 H allele is recessive to wild-type but is dominant to the previously known allele of scl-1 (now designated scl-1°). Strains carrying scl-1° fail to produce sclerotia and since its allele scl-1 H causes the formation of sclerotia having an abnormal proliferation of cells, particularly in the rind, it is suggested that the scl-1 gene may normally be involved in the control of the disposition and extent of tissue layers during sclerotium development.

The effect of topical crude coal tar treatment on unstimulated hairless hamster skin

Topical treatment of hairless hamster skin with crude coal tar has been shown to induce epidermal thickening, an increased labelling index in the basal cell layer, an elevation in NADP-dependent glucose-6-phosphate dehydrogenase activity throughout the epidermis, an increased squame count, comedo formation, and atrophy of the sebaceous glands. Ultraviolet light fluorescence microscopy of sections of treated skin suggests that the hair follicle is an important route for skin penetration by coal tar.

FERULIC ACID IN BARLEY CELL WALLS: A FLUORESCENCE STUDY

Cell walls isolated from barley endosperm have been examined using ultraviolet fluorescence microscopy in parallel with microspectrofluorimetry. The endosperm cell wall fragments exhibit a pale blue autofluorescence. The fluorescence emission spectrum of the walls closely corresponds to the spectrum of ferulic acid, having an emission maximum at a wavelength of 445 nm under the conditions used (excitation maximum at 365 nm). The results provide further evidence that ferulic acid-carbohydrate complexes are localized in barley endosperm cell walls. Similar complexes may be present in aleurone cell walls in relatively high concentrations.

Detection of bound ferulic acid in cell walls of the Gramineae by ultraviolet fluorescence microscopy

THE phenolic acids, ferulic and p-coumaric, are bound to cell walls of plants of the Gramineae (which include grasses and cereals) and it was thought that these acids were esterified to lignin and so occurred only in lignified cell walls1–4. But it has been shown recently that in cell walls of Lolium multifiorum Lam., which contain ferulic acid and a small amount of p-coumaric acid mainly as their trans isomers, the acids are esterified at their carboxyl groups to polysaccharides5–7. The digestibility of grasses by ruminants can be predicted by estimating the amounts of the acids released from the plant cell walls after treatment with a commercial cellulase preparation8. The acids could be important in influencing the degradation of plant organic matter in the rumen or in soil and may act as growth inhibitors of plant pathogens9. We now report results obtained by ultraviolet fluorescence microscopy, which indicate that ferulic acid is bound to polysaccharides of the walls of a wide variety of cell types of the Gramineae; these walls give a negative phloroglucinol–HCl test for lignin10.

Architecture and Deposition of Cellulin Granules inApodachlyaSp.

Cellulin, the unique chitin-glucan granules found in leptomitalean fungi, was investigated by cytochemical, interference contrast, ultraviolet fluorescence and electron microscopy. The concentric ring substructure, routinely observed by light microscopy observations of granules, was found to be present at the ultrastructural level. It was hypothesized that this concentricity was derived from alternating zones in which either chitin or 3-glucan was the predominant, but not necessarily exclusive, component. Electron microscopy demonstrated numerous cytoplasmic vesicles located on the granule perimeters or in close proximity. It was hypothesized that these vesicles deliver cellulin precursors and enzymes to the periphery of developing granules where the accretion of additional polysaccharide material occurs. No definitive observations were made demonstrating the nucleation of the granules.

Hormone-induced activation of target-specific lysosomes: acute translocation to the nucleus after administration of gonadal hormones in vivo.

SUMMARY Recent evidence from these laboratories has implicated the primary lysosomal population of specific target cells in the selective reception of steroid hormones at the cell periphery. This phenomenon was shown to be associated with covert labilization of the lysosomal bounding membrane. It has now been demonstrated that this interaction with trophic hormones results in rapid migration of lysosomes to a perinuclear position. Suspensions of nuclei were isolated from preputial glands of ovariectomized rats within short intervals after administration of gonadal hormone in vivo. Identification of cellular organelles by ultraviolet fluorescence microscopy was carried out on preparations subjected to intravital staining in vitro with acridine orange. Lysosomes were present in high concentrations in nuclear fractions of preputial glands from animals pretreated with oestradiol-17β, diethylstilboestrol, or testosterone, and essentially absent in preparations obtained from animals injected with oestradiol-17α or control solution. The response could be detected within 1 min of hormone administration, was obtained with as little as 0·1 μg hormone/100 g body wt, and was not observed in preparations from lung tissue. In the early stages of hormonal activation, lysosomes in preputial gland preparations formed adherent perinuclear clusters and appeared relatively intact. However, lysosome fragmentation and dissolution rapidly ensued and was accompanied by the appearance of polynuclear—multilysosomal aggregates. Concomitantly, isolated lysosome preparations subjected to enzymatic analyses revealed increased release from the particle-bound form of hydrolytic enzymes characteristic of these organelles. Progressive nuclear metachromasy was also observed after administration of the active hormones, suggesting the breakdown of macromolecules which yield products with enhanced capacity for binding acridine orange. These results suggested that modification of the nuclear surface and of intranuclear constituents, leading to altered adhesiveness and dye binding, respectively, may reflect the activity of structurally latent hydrolases released in situ from lysosomal membranes labilized by exposure to hormone. The present results support the concept that lysosomal function may be involved in the coupling of initial steroid—receptor interaction at the cell membrane with hormone-dependent events in specific target cells.

An evaluation of rhodamine-labeled lysozyme as a fluorescent stain for in situ soil bacteria.

Rhodamine-labeled lysozyme, in conjunction with fluorescein isothiocyanate conjugated to gelatin as a counterstain, was evaluated as a fluorescent stain for resident soil microorganisms. Preparations were observed by light-diffraction microscopy, transmitted incandescent-light microscopy, and reflected ultraviolet-fluorescence microscopy using a modified light-diffraction microscope, and by conventional transmitted incandescent and ultraviolet-fluorescence microscopy. Laboratory-grown microbial cultures superimposed on the resident soil microflora, as well as the non-dormant resident soil microorganisms, usually fluoresced properly when the stain and counterstain were applied to soil, and the blocking test with non-conjugated lysozyme was effective. What were assumed to be semidormant cells fluoresced to a lesser degree, and the blocking test was only partially effective. In contrast, the dormant resident soil microorganisms usually did not become stained by the methods used. A possible explanation is that a peripheral structural component surrounding many of the resident dormant cells in soil may have rendered their cell-wall substrate inaccessible to the enzyme conjugate.

Microorganisms in unamended soil as observed by various forms of microscopy and staining.

A light-diffraction microscope was modified to allow sequential viewing of the microorganisms in a soil smear by transmitted, reflected, and reflected-polarized incandescent light and by reflected ultraviolet light. Observations were also made by conventional incandescent and ultraviolet transmitted-light microscopy. All results for the various forms of bright-field microscopy with stained and unstained soils were in agreement, but they differed from the results obtained for two types of ultraviolet-fluorescence microscopy. The latter proved to be nonspecific for in situ soil microorganisms. Capsule-like areas were noted surrounding many of the resident microbial cells of soil when viewed by the various forms of bright-field microscopy. These areas could not be stained or removed by a variety of treatments, but they apparently often did take up stain after in situ soil growth had been initiated. It was concluded that these areas are not capsules but may represent a structural component of nonmultiplying microbial cells in soil.

Microorganisms in Unamended Soil as Observed by Various Forms of Microscopy and Staining 1

A light-diffraction microscope was modified to allow sequential viewing of the microorganisms in a soil smear by transmitted, reflected, and reflected-polarized incandescent light and by reflected ultraviolet light. Observations were also made by conventional incandescent and ultraviolet transmitted-light microscopy. All results for the various forms of bright-field microscopy with stained and unstained soils were in agreement, but they differed from the results obtained for two types of ultraviolet-fluorescence microscopy. The latter proved to be nonspecific for in situ soil microorganisms. Capsule-like areas were noted surrounding many of the resident microbial cells of soil when viewed by the various forms of bright-field microscopy. These areas could not be stained or removed by a variety of treatments, but they apparently often did take up stain after in situ soil growth had been initiated. It was concluded that these areas are not capsules but may represent a structural component of nonmultiplying microbial cells in soil.

Large bodies of Mycoplasma and L-form organisms.

The large bodies of various Mycoplasma and L-form organisms were studied by ultraviolet fluorescence microscopy of preparations stained with various fluorochromes. Primuline and Thioflavine S specifically stained the outer portion or rim of the large bodies, and the fluorescence characteristics of the stained bodies differed from those for other microorganisms and for spheroplasts and protoplasts. Small granular structures similar in size and morphology to minimal reproductive units were observed within some of the large bodies by phase microscopy and by fluorescence microscopy with acridine orange or Coriphosphine O. Micromanipulation probing of the large bodies revealed their elastic nature; many of the large bodies could be subdivided into two or more smaller circular bodies, each retaining the fluorescence staining properties of the parent body. Under these conditions, however, a few of the large bodies were ruptured, leaving the stainable outer boundary area as a stable residual structure. The large bodies were somewhat resistant to various rigorous treatments normally employed to eliminate viability of Mycoplasma and L-form cultures. Structures similr to large bodies were observed in various natural tissues, and structures resembling large bodies in size, morphology, fluorescence staining characteristics, and reaction to micromanipulation probing were reconstructed from an acetone extract of egg yolk. Overall, the large bodies of Mycoplasma and L-form organisms appeared to be structures resulting from accumulations of metabolic by-products and medium components within or on which minimal reproductive units had become entrapped, although it could not be ruled out that they might be defined structures specifically formed during culture as protective lipoidal sacs for the minimal reproductive units.

The use of ultra-violet fluorescence microscopy in the study of the antiblastoma properties of the blood serum

The use of ultra-violet fluorescence microscopy in the study of the antiblastoma properties of the blood serum

ABUNDANT MICROORGANISM IN SOIL.

The presence in soil of large numbers of a catalase-negative, microaerophilic, coccoid microorganism was demonstrated. Use of media of high nutrient value, without incorporation of inhibitors, and growth in the absence of antagonistic microorganisms were utilized to isolate this organism from soil dilutions greater than those providing growth by other means. The organism described does not grow on soil extract agars and is missed by conventional counting techniques for soil organisms. On the basis of morphological and growth characteristics, this organism appears to have at least some taxonomic relationships to the families Actinomycetaceae and Mycobacteriaceae. It is proposed that this organism makes up much of the coccoid microflora of soil as observed by light and ultraviolet fluorescence microscopy.

Abundant Microorganism in Soil1

The presence in soil of large numbers of a catalase-negative, microaerophilic, coccoid microorganism was demonstrated. Use of media of high nutrient value, without incorporation of inhibitors, and growth in the absence of antagonistic microorganisms were utilized to isolate this organism from soil dilutions greater than those providing growth by other means. The organism described does not grow on soil extract agars and is missed by conventional counting techniques for soil organisms. On the basis of morphological and growth characteristics, this organism appears to have at least some taxonomic relationships to the families Actinomycetaceae and Mycobacteriaceae. It is proposed that this organism makes up much of the coccoid microflora of soil as observed by light and ultraviolet fluorescence microscopy.

Illumination of micromanipulator tools in ultraviolet fluorescence microscopy.

Illumination of micromanipulator tools in ultraviolet fluorescence microscopy.

Porphyrin Fluorescence in the Livers of Pellagrins in Relation to Ultra-Violet Light

THE examination, by ultra-violet fluorescence microscopy, of frozen sections of fragments of livers removed by an improved biopsy procedure1 from twenty African pellagrins, soon after admission to hospital, revealed the presence in eight cases of an intense scarlet red fluorescence. This fluorescence was localized to the hepatic cells, and, when severe, could involve the entire lobule. When the fluorescent material was dissolved in the fat droplets in the hepatic cells, these assumed an intense crimson colour.