Imino–Phenolic–Pyridyl Conjugates of Calix[4]arene (L1 and L2) as Primary Fluorescence Switch-on Sensors for Zn2+ in Solution and in HeLa Cells and the Recognition of Pyrophosphate and ATP by [ZnL2]

Uranyl acetate has been used as an electron stain for en bloc staining as well as for staining ultrathin sections in conjunction with various lead stains (Fig. 1). Present studies reveal that various platinum compounds also show promise as electron stains. Certain platinum compounds have been shown to be effective anti-tumor agents. Of particular interest are the compounds with either uracil or thymine as one of the ligands (cis-Pt(II)-uracil; cis-Pt(II)-thymine). These compounds are amorphous, highly soluble in water and often exhibit an intense blue coloration. These compounds show enough electron density to be used as stains for electron microscopy. Most of the studies are based on various cell lines (human AV, cells, human lymphoma cells, KB cells, Sarcoma-180 ascites cells, chick fibroblasts and HeLa cells) while studies on tissue blocks are in progress.

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Electron Microscopy of Mycoplasma Pneumoniae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065341 ◽

1971 ◽

Vol 29 ◽

pp. 258-259 ◽

Cited By ~ 1

Author(s):

E. S. Boatman ◽

G. E. Kenny

Keyword(s):

Electron Microscopy ◽

Light Microscopy ◽

Growth Phase ◽

Hela Cells ◽

Sulfonic Acid ◽

Gamma Globulin ◽

Horse Serum ◽

Morphological Aspects ◽

The Family

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.

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Use of Uranium-Labeled Antibodies for Electron Microscopic Localization of Various Antigens in Mammalian Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060696 ◽

1967 ◽

Vol 25 ◽

pp. 136-137

Author(s):

J. P. Petrali ◽

E. J. Donati ◽

L. A. Sternberger

Keyword(s):

Endoplasmic Reticulum ◽

Hela Cells ◽

Mammalian Cells ◽

Specific Antiserum ◽

Electron Microscopic ◽

E Coli ◽

Cytoplasmic Membranes ◽

Viral Progeny ◽

Ultrathin Sections ◽

Electron Microscopic Localization

Specific contrast is conferred to subcellular antigen by applying purified antibodies, exhaustively labeled with uranium under immunospecific protection, to ultrathin sections. Use of Seligman’s principle of bridging osmium to metal via thiocarbohydrazide (TCH) intensifies specific contrast. Ultrathin sections of osmium-fixed materials were stained on the grid by application of 1) thiosemicarbazide (TSC), 2) unlabeled specific antiserum, 3) uranium-labeled anti-antibody and 4) TCH followed by reosmication. Antigens to be localized consisted of vaccinia antigen in infected HeLa cells, lysozyme in monocytes of patients with monocytic or monomyelocytic leukemia, and fibrinogen in the platelets of these leukemic patients. Control sections were stained with non-specific antiserum (E. coli).In the vaccinia-HeLa system, antigen was localized from 1 to 3 hours following infection, and was confined to degrading virus, the inner walls of numerous organelles, and other structures in cytoplasmic foci. Surrounding architecture and cellular mitochondria were unstained. 8 to 14 hours after infection, antigen was localized on the outer walls of the viral progeny, on cytoplasmic membranes, and free in the cytoplasm. Staining of endoplasmic reticulum was intense and focal early, and weak and diffuse late in infection.

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Exogeneous factors are not necessary in attachment, spreading and polarization of hela cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082418 ◽

1978 ◽

Vol 36 (2) ◽

pp. 310-311

Author(s):

W. Liebrich

Keyword(s):

Hela Cells ◽

Calf Serum ◽

Glass Tube ◽

Serum Free Medium ◽

Nacl Solution ◽

Free Medium ◽

Minimum Essential Medium ◽

Serum Free ◽

All Solutions ◽

Glass Support

HeLa cells were grown for 2-3 days in EAGLE'S minimum essential medium with 10% calf serum (S-MEM; Seromed, München) and then incubated for 24 hours in serum free medium (MEM). After detaching the cells with a solution of 0. 14 % EDTA and 0. 07 % trypsin (Difco, 1 : 250) they were suspended in various solutions (S-MEM = control, MEM, buffered salt solutions with or without Me++ions, 0. 9 % NaCl solution) and allowed to settle on glass tube slips (Leighton-tubes). After 5, 10, 15, 20, 25, 30, 1 45, 60 minutes 2, 3, 4, 5 hours cells were prepared for scanning electron microscopy as described by Paweletz and Schroeter. The preparations were examined in a Jeol SEM (JSM-U3) at 25 KV without tilting.The suspended spherical HeLa cells are able to adhere to the glass support in all solutions. The rate of attachment, however, is faster in solutions without serum than in the control. The latter is in agreement with the findings of other authors.

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Human Adenovirus Uptake by Preirnplantation Mouse Embryos

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094607 ◽

1972 ◽

Vol 30 ◽

pp. 268-269

Author(s):

D. G. Chase ◽

W. Winters ◽

L. Piko

Keyword(s):

Hela Cells ◽

Human Adenovirus ◽

Mouse Embryos ◽

Equilibrium Density ◽

Cell Stage ◽

Virus Attachment ◽

Preimplantation Mouse Embryos ◽

Embryo Culture Medium ◽

Preimplantation Mouse ◽

Mouse Cells

Although the outlines of human adenovirus entry and uncoating in HeLa cells has been clarified in recent electron microscope studies, several details remain unclear or controversial. Furthermore, morphological features of early interactions of human adenovirus with non-permissive mouse cells have not been extensively documented. In the course of studies on the effects of human adenoviruses type 5 (AD-5) and type 12 on cultured preimplantation mouse embryos we have examined virus attachment, entry and uncoating. Here we present the ultrastructural findings for AD-5.AD-5 was grown in HeLa cells and purified by successive velocity gradient and equilibrium density gradient centrifugations in CsCl. After dialysis against PBS, virus was sedimented and resuspended in embryo culture medium. Embryos were placed in culture at the 2-cell stage in Brinster's medium.

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Temporal and spatial interrelationships of confronting cisternae to nuclear envelope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125051 ◽

1992 ◽

Vol 50 (1) ◽

pp. 930-931

Author(s):

John R. Palisano

Keyword(s):

Endoplasmic Reticulum ◽

Nuclear Envelope ◽

Tumor Cells ◽

Hela Cells ◽

Microscopic Investigation ◽

Electron Microscopic Investigation ◽

Serial Sections ◽

Electron Microscopic ◽

Fetal Rat ◽

Temporal And Spatial

Although confronting cistemae (CC) have been observed in a variety of tumor cells and normal fetal rat, mouse, and human epithelial tissues, little is known about their origin or role in mitotic cells. While several investigators have suggested that CC arise from nuclear envelope (NE) folding back on itself during prophase, others have suggested that CC arise when fragments of NE pair with endoplasmic reticulum. An electron microscopic investigation of 0.25 um thick serial sections was undertaken to examine the origin of CC in HeLa cells.

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Properties of the human ezrin gene enhancer in HeLa cells: position, orientation and promoter dependence

Cell Biology International ◽

10.1042/cbi034s045c ◽

2010 ◽

Vol 34 (8) ◽

pp. S45-S45

Author(s):

Shu‑Ying Gao ◽

Jie Yu ◽

Yan‑Peng Dai

Keyword(s):

Hela Cells ◽

Gene Enhancer

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A View of the Lexical–Grammatical Link in Young Latinos With Specific Language Impairment Using Language-Specific and Conceptual Measures

Journal of Speech Language and Hearing Research ◽

10.1044/2019_jslhr-l-18-0315 ◽

2019 ◽

Vol 62 (6) ◽

pp. 1775-1786 ◽

Cited By ~ 2

Author(s):

Lucía I. Méndez ◽

Gabriela Simon-Cereijido

Keyword(s):

Low Income ◽

Language Impairment ◽

Specific Language Impairment ◽

L2 Acquisition ◽

Cross Sectional ◽

Specific Language ◽

Vocabulary Skills ◽

In The Beginning ◽

Study Participants ◽

L1 And L2

Purpose This study investigated the nature of the association of lexical–grammatical abilities within and across languages in Latino dual language learners (DLLs) with specific language impairment (SLI) using language-specific and bilingual measures. Method Seventy-four Spanish/English–speaking preschoolers with SLI from preschools serving low-income households participated in the study. Participants had stronger skills in Spanish (first language [L1]) and were in the initial stages of learning English (second language [L2]). The children's lexical, semantic, and grammar abilities were assessed using normative and researcher-developed tools in English and Spanish. Hierarchical linear regressions of cross-sectional data were conducted using measures of sentence repetition tasks, language-specific vocabulary, and conceptual bilingual lexical and semantic abilities in Spanish and English. Results Results indicate that language-specific vocabulary abilities support the development of grammar in L1 and L2 in this population. L1 vocabulary also contributes to L2 grammar above and beyond the contribution of L2 vocabulary skills. However, the cross-linguistic association between vocabulary in L2 and grammar skills in the stronger or more proficient language (L1) is not observed. In addition, conceptual vocabulary significantly supported grammar in L2, whereas bilingual semantic skills supported L1 grammar. Conclusions Our findings reveal that the same language-specific vocabulary abilities drive grammar development in L1 and L2 in DLLs with SLI. In the early stages of L2 acquisition, vocabulary skills in L1 also seem to contribute to grammar skills in L2 in this population. Thus, it is critical to support vocabulary development in both L1 and L2 in DLLs with SLI, particularly in the beginning stages of L2 acquisition. Clinical and educational implications are discussed.

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