On the Structure, Division, and Systematic Position of Trichomonas vaginalis Donné, with a Note on its Methods of Feeding

1947 ◽  
Vol s3-88 (1) ◽  
pp. 79-98
Author(s):  
R. S. HAWES

1. Trichomonas vaginalis has been cultivated on various media and a simple method of maintaining cultures on Boeck and Drbohlav's egg-Ringer-albumen medium is described. 2. The feeding methods of the flagellates in culture have been studied and some evidence of extracellular digestion is recorded. 3. When cultivated on media deficient in carbohydrate, T. vaginalis is reduced to the dimensions of T. hominis, but when adequately fed it maintains its distinctively larger size. Out of forty-eight strains of T. vaginalis, only two developed in culture the long undulating membrane and free posterior flagellum typical of T. hominis in nature. 4. The structure of T. vaginalis has been reinvestigated. (i) It differs constantly and significantly from the intestinal trichomonads of man in size, nuclear organization, and the form of the axostyle and basal fibre, (ii) It also differs from T. hominis in the characters of its parabasal apparatus and cytoplasmic inclusions, and, in nature, in the length of its undulating membrane and in lacking a free posterior flagellum, but for reasons discussed in the text these points are at present considered less reliable in diagnosis than those given under 4 (i). 5. It is concluded that T. vaginalis is a species distinct from all other human trichomonads. 6. The method of division has been described. In general, it follows the same course as T. hominis, but separation of the old, and growth of the new, cytoplasmic structures occurs somewhat later in T. vaginalis, and the old axostyle is retained throughout division. There are five chromosomes, formed during prophase from aggregations of extra-karyosomatic granules.

2002 ◽  
Vol 126 (1) ◽  
pp. 93-96
Author(s):  
Karen L. Grogg ◽  
Chandrashekar Padmalatha ◽  
Kevin O. Leslie

Abstract We report a bronchial carcinoid tumor with distinctive, cytoplasmic, rod-shaped crystalloid inclusions that were visible by light microscopy. These cytoplasmic structures were immunoreactive with antibodies against chromogranin A and synaptophysin in paraffin-embedded tissue. Ultrastructural studies showed them to be paracrystalline in nature and located within lysosomes. This case highlights an interesting, and potentially confusing, histologic manifestation in an otherwise typical bronchial carcinoid tumor.


1979 ◽  
Vol 16 (1) ◽  
pp. 6-17 ◽  
Author(s):  
S. D. Kosanke ◽  
K. R. Pierce ◽  
W. K. Read

The neurons and glial cells of 1- to 140-day-old pigs with GM2-gangliosidosis had membranous cytoplasmic inclusion bodies. These bodies appeared as small vacuolated cytoplasmic structures in paraffin-embedded, hematoxylin and eosin-stained sections and as solid, dark, round granules in 1-micrometer sections embedded in plastic and stained with toluidine blue. Ultrastructurally, the cytoplasmic inclusion bodies appeared as round, dense structures from 0.6 to 1.2 micrometers in diameter, that were filled with various amounts of small to large arrays of membranous lamellae. The cortical neuronal inclusions were seen initially as lysosomes containing a small amount of particulate material. The appearance of these inclusions changed as they progressed through different configurational stages. Inclusions resembled the granulomembranous body, the zebra body, possibly other intermediate forms and, finally, the classical membranous cytoplasmic body. The cytoplasmic inclusions in glial cells resembled membranovesicular bodies and, although also of apparent lysosomal origin, were morphologically different from the neuronal inclusions. The morphologic lesions in the neurons and glial cells of the affected pigs were similar to those described for human gangliosidoses.


A great deal has been published in recent years upon cytoplasmic structures appearing in fixed material. Among them, those described as Golgi elements, bodies, apparatus and dictyosomes have, perhaps, received most attention. It is unfortunate that these, together with other structures, have been classed as “Cytoplasmic inclusions” (Gatenby, 1917-21, and others). This is a misleading term which obviously does not convey the meaning intended.. The structures or bodies referred to are supposed to arise in the cytoplasm,, or, being credited with the power of multiplication and development, to be handed on in the cytoplasm from one cell generation to another. The Golgi apparatus is described as being “ of very wide distribution among the cells of higher animals, and is known in the Protozoa, • everywhere showing the same general characters ; and there is reason to believe that the same may be true of plant cells, though considerable doubt concerning this still exists.” (Wilson, 1925.) The apparatus or elements may vary from a localised, network to scattered granules, curved rods, plates or ring-like bodies. The Golgi elements are soluble in acetic acid, and hence it has been assumed that they escaped the notice of earlier observers. No acetic acid, a very usual ingredient of fixatives, is used in the treatment of material in which Golgi elements are to be demonstrated. While chondriosomes, in suitably fixed preparations, darken in osmic acid (OsO 4 ), the Golgi apparatus appears intensely black; hence the two are sometimes supposed to be chemically related. It is claimed that chondriosomes may be differentiated from Golgi bodies by washing the preparation that has been treated with osmic acid in turpentine, when the chondriosomes turn brown, the Golgi bodies remaining intensely black. (Gatenby, 1921.) The chondriosomes, after fixation, are not dependent for their demonstration upon reduction of the reagent used (e. g., OsO 4 or A g NO 3 .), but will stain with certain aniline dyes. Hence it seems probable that there is a definite difference between them and the Golgi elements. [It seems likely that many of the structures produced by the OsO 4 process and labelled chondriosomes are not the same as those demonstrated by other methods. ( April 12, 1927.)]


2020 ◽  
Vol 6 (4) ◽  
pp. 44
Author(s):  
Michelle Aillaud ◽  
Leon N Schulte

While the important functions of long noncoding RNAs (lncRNAs) in nuclear organization are well documented, their orchestrating and architectural roles in the cytoplasmic environment have long been underestimated. However, recently developed fractionation and proximity labelling approaches have shown that a considerable proportion of cellular lncRNAs is exported into the cytoplasm and associates nonrandomly with proteins in the cytosol and organelles. The functions of these lncRNAs range from the control of translation and mitochondrial metabolism to the anchoring of cellular components on the cytoskeleton and regulation of protein degradation at the proteasome. In the present review, we provide an overview of the functions of lncRNAs in cytoplasmic structures and machineries und discuss their emerging roles in the coordination of the dense intracellular milieu. It is becoming apparent that further research into the functions of these lncRNAs will lead to an improved understanding of the spatiotemporal organization of cytoplasmic processes during homeostasis and disease.


Author(s):  
K.-H. Herrmann ◽  
E. Reuber ◽  
P. Schiske

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.


Author(s):  
S. E. Miller ◽  
G. B. Hartwig ◽  
R. A. Nielsen ◽  
A. P. Frost ◽  
A. D. Roses

Many genetic diseases can be demonstrated in skin cells cultured in vitro from patients with inborn errors of metabolism. Since myotonic muscular dystrophy (MMD) affects many organs other than muscle, it seems likely that this defect also might be expressed in fibroblasts. Detection of an alteration in cultured skin fibroblasts from patients would provide a valuable tool in the study of the disease as it would present a readily accessible and controllable system for examination. Furthermore, fibroblast expression would allow diagnosis of fetal and presumptomatic cases. An unusual staining pattern of MMD cultured skin fibroblasts as seen by light microscopy, namely, an increase in alcianophilia and metachromasia, has been reported; both these techniques suggest an altered glycosaminoglycan metabolism An altered growth pattern has also been described. One reference on cultured skin fibroblasts from a different dystrophy (Duchenne Muscular Dystrophy) reports increased cytoplasmic inclusions seen by electron microscopy. Also, ultrastructural alterations have been reported in muscle and thalamus biopsies from MMD patients, but no electron microscopical data is available on MMD cultured skin fibroblasts.


Author(s):  
Dean A. Handley ◽  
Jack T. Alexander ◽  
Shu Chien

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.


Author(s):  
F. A. Durum ◽  
R. G. Goldman ◽  
T. J. Bolling ◽  
M. F. Miller

CMP-KDO synthetase (CKS) is an enzyme which plays a key role in the synthesis of LPS, an outer membrane component unique to gram negative bacteria. CKS activates KDO to CMP-KDO for incorporation into LPS. The enzyme is normally present in low concentrations (0.02% of total cell protein) which makes it difficult to perform large scale isolation and purification. Recently, the gene for CKS from E. coli was cloned and various recombinant DNA constructs overproducing CKS several thousandfold (unpublished data) were derived. Interestingly, no cytoplasmic inclusions of overproduced CKS were observed by EM (Fig. 1) which is in contrast to other reports of large proteinaceous inclusion bodies in various overproducing recombinant strains. The present immunocytochemical study was undertaken to localize CKS in these cells.Immune labeling conditions were first optimized using a previously described cell-free test system. Briefly, this involves soaking small blocks of polymerized bovine serum albumin in purified CKS antigen and subjecting them to various fixation, embedding and immunochemical conditions.


2001 ◽  
Vol 7 (S2) ◽  
pp. 578-579
Author(s):  
David W. Knowles ◽  
Sophie A. Lelièvre ◽  
Carlos Ortiz de Solόrzano ◽  
Stephen J. Lockett ◽  
Mina J. Bissell ◽  
...  

The extracellular matrix (ECM) plays a critical role in directing cell behaviour and morphogenesis by regulating gene expression and nuclear organization. Using non-malignant (S1) human mammary epithelial cells (HMECs), it was previously shown that ECM-induced morphogenesis is accompanied by the redistribution of nuclear mitotic apparatus (NuMA) protein from a diffuse pattern in proliferating cells, to a multi-focal pattern as HMECs growth arrested and completed morphogenesis . A process taking 10 to 14 days.To further investigate the link between NuMA distribution and the growth stage of HMECs, we have investigated the distribution of NuMA in non-malignant S1 cells and their malignant, T4, counter-part using a novel model-based image analysis technique. This technique, based on a multi-scale Gaussian blur analysis (Figure 1), quantifies the size of punctate features in an image. Cells were cultured in the presence and absence of a reconstituted basement membrane (rBM) and imaged in 3D using confocal microscopy, for fluorescently labeled monoclonal antibodies to NuMA (fαNuMA) and fluorescently labeled total DNA.


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