Surface topography of normal and neoplastic human anterior pituitary cells maintained in vitro

✓ Pituitary tissues were obtained from 25 patients who underwent surgery for excision of pituitary macroadenomas, selective excision of microadenomas, or removal of a normal gland for palliation of metastatic cancer. Cells thus obtained were maintained in vitro for varying intervals, fixed, and examined by light (phase contrast), microscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Previous SEM reports indicate that surface topography of in vitro neoplastic cells displays features that may correlate with neoplastic behavior. Cultured normal and pituitary tumor cells did not display these surface differences, with one exception, a prolactin-secreting microadenoma. Characteristic patterns for the cell populations were identified. Certain cell types appeared in all the cultures: 1) large and small granule-containing cells; 2) flat and irregular agranular cells; 3) spindle-shaped cells; and 4) spherical, irregularly surfaced cells. In one case of an endocrine-inactive juvenile pituitary chromophobe adenoma, unique cells were observed. Surface topography did not appear to be of predictive value in determining the neoplastic character of pituitary tumors.

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Antimicrobial Properties of a Chitosan Dextran-Based Hydrogel for Surgical Use

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05463-11 ◽

2011 ◽

Vol 56 (1) ◽

pp. 280-287 ◽

Cited By ~ 80

Author(s):

Manal A. Aziz ◽

Jaydee D. Cabral ◽

Heather J. L. Brooks ◽

Stephen C. Moratti ◽

Lyall R. Hanton

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Bacterial Species ◽

Antimicrobial Properties ◽

Sinus Surgery ◽

Peptide Bonds ◽

Content Type ◽

E Coli ◽

Transmission Electron

ABSTRACTA chitosan dextran-based (CD) hydrogel, developed for use in endoscopic sinus surgery, was tested for antimicrobial activityin vitroagainst a range of pathogenic microorganisms. The microdilution technique was used to determine minimum inhibitory, minimum bactericidal, and minimum fungicidal concentrations. In addition, the time-kill efficacy of CD hydrogel was determined for two bacterial species. Scanning and transmission electron microscopy were carried out to elucidate the antimicrobial mechanism of this compound. CD hydrogel was found to be effective againstStaphylococcus aureus,Streptococcus pyogenes,Escherichia coli, andClostridium perfringensat its surgical concentration of 50,000 mg/liter. Minimum bactericidal concentrations ranged from 2,000 to 50,000 mg/liter. Dextran aldehyde (DA) was found to be the antimicrobial component of the CD hydrogel with MBC ranging from 2,000 to 32,000 mg/liter.S. aureusappeared to be killed at a slightly faster rate thanE. coli. Candida albicansandPseudomonas aeruginosawere more resistant to CD hydrogel and DA. Scanning and transmission electron microscopy ofE. coliandS. aureusincubated with CD hydrogel and DA alone revealed morphological damage, disrupted cell walls, and loss of cytosolic contents, compatible with the proposed mode of action involving binding to cell wall proteins and disruption of peptide bonds. Motility and chemotaxis tests showedE. colito be inhibited when incubated with DA. The antibacterial activity of CD hydrogel may make it a useful postsurgical aid at other body sites, especially where there is a risk of Gram-positive infections.

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Arsenic Trioxide Negatively Affects Echinococcus granulosus

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.04340-14 ◽

2015 ◽

Vol 59 (11) ◽

pp. 6946-6951 ◽

Cited By ~ 6

Author(s):

Bo Wang ◽

Yufeng Jiang ◽

Zhuo Wang ◽

Fangfang Li ◽

Guoqiang Xing ◽

...

Keyword(s):

Electron Microscopy ◽

Arsenic Trioxide ◽

Echinococcus Granulosus ◽

Treatment Options ◽

Small Sample ◽

Content Type ◽

Transmission Electron ◽

New Strategy

ABSTRACTSpillage of cyst contents during surgery is the major cause of recurrences of hydatidosis, also called cystic echinococcosis (CE). Currently, many scolicidal agents are used for inactivation of the cyst contents. However, due to complications in the use of those agents, new and more-effective treatment options are urgently needed. The aim of this study was to investigate thein vitroefficacy of arsenic trioxide (ATO) againstEchinococcus granulosusprotoscolices. Protoscolices ofE. granulosuswere incubatedin vitrowith 2, 4, 6, and 8 μmol/liter ATO; viability of protoscolices was assessed daily by microscopic observation of movements and 0.1% eosin staining. A small sample from each culture was processed for scanning and transmission electron microscopy. ATO demonstrated a potent ability to kill protoscolices, suggesting that ATO may represent a new strategy in treating hydatid cyst echinococcosis. However, thein vivoefficacy and possible side effects of ATO need to be explored.

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Expression of X hapten immunoreactivity by human and rat adenohypophyseal cells

Journal of Neurosurgery ◽

10.3171/jns.1988.68.6.0938 ◽

1988 ◽

Vol 68 (6) ◽

pp. 938-946 ◽

Cited By ~ 6

Author(s):

Joseph R. Madsen ◽

Dora W. Hsu ◽

E. Tessa Hedley-Whyte ◽

William D. Matthew

Keyword(s):

Growth Hormone ◽

Pituitary Tumors ◽

Thyroid Stimulating Hormone ◽

Pituitary Cells ◽

Cell Hyperplasia ◽

Altered Expression ◽

Content Type ◽

Normal Rat ◽

Double Label ◽

Human Anterior Pituitary

✓ The monoclonal antibody Hy2D4 was found to label a previously undescribed subset of rat and human anterior pituitary cells. The antibody binding site appears to be a carbohydrate moiety previously named “X hapten.” Double-label immunofluorescence studies in both normal rat and postmortem human pituitaries showed that this antigen is distributed on a subset of adrenocorticotropic hormone (ACTH)-positive cells, but is not detectable in cells immunoreactive for growth hormone, prolactin (PRL), thyroid-stimulating hormone, or luteinizing hormone. Since X hapten labeling revealed a biological subdivision of corticotroph cells, it was expected that some ACTH-positive tumors would be immunoreactive, but that tumors of other hormonal types would be negative. Instead, in 21 surgical specimens examined, tumors of all hormonal types were found to show immunoreactivity. To determine whether experimental proliferative changes in the pituitary could explain the shift in the cell type expressing the antigen, PRL-cell hyperplasia was induced in rats through chronic (8-week) exposure to diethylstilbestrol. The fraction of X-positive cells increased in these hyperplastic glands almost ninefold and, as in human adenomas, many non-corticotroph cells expressed the X marker in this model. However, the non-corticotroph cells expressing X were predominantly growth hormone cells, not the proliferative PRL cells. Thus, expression of the antigen does not necessarily imply that a cell is in a proliferative mode. While it is not known what role an altered expression of this antigen might play, the antibody offers a probe into cellular biology of human and experimental pituitary tumors.

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The acellular stroma of the chick cornea inhibits melanogenesis of the neural-crest-derived cells that colonize it.

Development ◽

10.1242/dev.86.1.143 ◽

1985 ◽

Vol 86 (1) ◽

pp. 143-154

Author(s):

Steven Campbell ◽

Jonathan B. L. Bard

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Extracellular Matrix ◽

Neural Crest ◽

Corneal Stroma ◽

Cell Types ◽

Brown Pigment ◽

Transmission Electron ◽

Wide Range

Neural crest (NC) cells from the periorbital mesenchyme (POM) invade the acellular stroma of the chick cornea at stage 27 of development (∼6 days). The invading cells become collagenproducing fibroblasts while the NC cells remaining in the POM differentiate into a wide range of cell types, the most easily recognizable of which is the pigment-producing melanocyte. In this paper, we report observations on the differentiation in vitro of cells within and migrating from explants of corneal stroma and compare their behaviour with that of cells within and migrating from explants of the POM. In ∼70% of cases, POM explants produced black, eumelanin pigmentation within 2–3 days in culture and gave rise to a mixed outgrowth of fibroblasts and melanoblasts that produced brown pigment. In no case, however, did a corneal explant produce black pigment (so demonstrating that any POM contamination was negligible). However, in 28% of cultures from stage-27 and -28 corneas, some of the cells in the outgrowth contained brown pigment indistinguishable from that produced by the POM control, although the majority of the cells in each case were fibroblasts. Two lines of investigation demonstrated that this pigment was melanin: first, transmission electron microscopy showed that the pigment organelles were incompletely melanized, granular melanosomes; second, tests designed to demonstrate the presence of lipofuscin, an alternative pigment, proved negative. Migrating cells from older corneas, in contrast, showed no evidence of even the first stages of melanogenesis. These results show, first, that some of the NC cells that invade the cornea are at least bipotent and hence representative of the POM population rather than being a unique subgroup and, second, that the acellular stroma of the cornea determines the state of differentiation of the NC cells that colonize it. The results thus provide an unequivocal demonstration that extracellular matrix can induce postmigratory NC cells to differentiate into fibroblasts.

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Morphology and Transcriptome Analysis of Nosema bombycis Sporoplasm and Insights into the Initial Infection of Microsporidia

mSphere ◽

10.1128/msphere.00958-19 ◽

2020 ◽

Vol 5 (1) ◽

Cited By ~ 1

Author(s):

Qiang He ◽

Jian Luo ◽

Jin-Zhi Xu ◽

Chun-xia Wang ◽

Xian-zhi Meng ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Host Cell ◽

Transcriptome Analysis ◽

Molecular Characteristics ◽

Content Type ◽

Nosema Bombycis ◽

Obligate Intracellular ◽

Transmission Electron

ABSTRACT Microsporidia are obligate intracellular parasites that infect a wide variety of host organisms, including humans. The sporoplasm is the initial stage of microsporidian infection and proliferation, but its morphological and molecular characteristics are poorly understood. In this study, the sporoplasm of Nosema bombycis was successfully isolated and characterized after the induction of spore germination in vitro. The sporoplasm was spherical, 3.64 ± 0.41 μm in diameter, had the typical two nuclei, and was nonrefractive. Scanning and transmission electron microscopy analyses revealed that the sporoplasm was surrounded by a single membrane, and the cytoplasm was usually filled with relatively homogeneous granules, possibly ribosomes, and contained a vesicular structure comprising a concentric ring and coiled tubules. Propidium iodide staining revealed that the sporoplasm membrane showed stronger membrane permeability than did the cell plasma membrane. Transmission electron microscopy (TEM) revealed that the sporoplasm can gain entry to the host cell by phagocytosis. Transcriptome analysis of mature spores and sporoplasms showed that 541 significantly differentially expressed genes were screened (adjusted P value [Padj] < 0.05), of which 302 genes were upregulated and 239 genes were downregulated in the sporoplasm. The majority of the genes involved in trehalose synthesis metabolism, glycolysis, and the pentose phosphate pathway were downregulated, whereas 10 transporter genes were upregulated, suggesting that the sporoplasm may inhibit its own carbon metabolic activity and obtain the substances required for proliferation through transporter proteins. This study represents the first comprehensive and in-depth investigation of the sporoplasm at the morphological and molecular levels and provides novel insights into the biology of microsporidia and their infection mechanism. IMPORTANCE Once awoken from dormancy, the cellular matter of microsporidia is delivered directly into the host cell cytoplasm through the polar tube. This means that the microsporidia are difficult to study biologically in their active state without a contaminating signal from the host cell. Sporoplasm is a cell type of microsporidia in vitro, but relatively little attention has been paid to the sporoplasm in the past 150 years due to a lack of an effective separation method. Nosema bombycis, the first reported microsporidium, is a type of obligate intracellular parasite that infects silkworms and can be induced to germinate in alkaline solution in vitro. We successfully separated the N. bombycis sporoplasm in vitro, and the morphological and structural characteristics were investigated. These results provide important insight into the biology and pathogenesis of microsporidia and potentially provide a possible strategy for genetic manipulation of microsporidia targeting the sporoplasm.

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Maytansine-Induced Mitotic Arrest in Human Lymphoblasts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079747 ◽

1977 ◽

Vol 35 ◽

pp. 460-461

Author(s):

Tai-Te Chao ◽

John Sullivan ◽

Awtar Krishan

Keyword(s):

Electron Microscopy ◽

Cell Cycle ◽

Transmission Electron Microscopy ◽

Tubulin Polymerization ◽

Vinca Alkaloids ◽

Antimitotic Activity ◽

Transmission Electron ◽

Flow Microfluorometry ◽

Brain Tubulin

Maytansine, a novel ansa macrolide (1), has potent anti-tumor and antimitotic activity (2, 3). It blocks cell cycle traverse in mitosis with resultant accumulation of metaphase cells (4). Inhibition of brain tubulin polymerization in vitro by maytansine has also been reported (3). The C-mitotic effect of this drug is similar to that of the well known Vinca- alkaloids, vinblastine and vincristine. This study was carried out to examine the effects of maytansine on the cell cycle traverse and the fine struc- I ture of human lymphoblasts.Log-phase cultures of CCRF-CEM human lymphoblasts were exposed to maytansine concentrations from 10-6 M to 10-10 M for 18 hrs. Aliquots of cells were removed for cell cycle analysis by flow microfluorometry (FMF) (5) and also processed for transmission electron microscopy (TEM). FMF analysis of cells treated with 10-8 M maytansine showed a reduction in the number of G1 cells and a corresponding build-up of cells with G2/M DNA content.

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The Ultrastructure of Lymphocytic Hypophysitis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098824 ◽

1981 ◽

Vol 39 ◽

pp. 466-467

Author(s):

S.L. Asa ◽

K. Kovacs ◽

J. M. Bilbao ◽

R. G. Josse ◽

K. Kreines

Keyword(s):

Electron Microscopy ◽

Plasma Cells ◽

Secretory Granules ◽

Sella Turcica ◽

Uranyl Acetate ◽

Lymphocytic Hypophysitis ◽

Pituitary Cells ◽

Transmission Electron ◽

Ultrathin Sections ◽

Mass Lesions

Seven cases of lymphocytic hypophysitis in women have been reported previously in association with various degrees of hypopituitarism. We report two pregnant patients who presented with mass lesions of the sella turcica, clinically mimicking pituitary adenoma. However, pathologic examination revealed extensive infiltration of the anterior pituitary by lymphocytes and plasma cells with destruction of the gland. To our knowledge, the ultrastructural features of lymphocytic hypophysitis have not been studied so far.For transmission electron microscopy, tissue from surgical specimens was fixed in glutaraldehyde, postfixed in OsO4, dehydrated and embedded in epoxy-resin. Ultrathin sections were stained with uranyl acetate and lead citrate and examined with a Philips 300 electron microscope.Electron microscopy revealed adenohypophysial cells of all types exhibiting varying degrees of injury. In the areas of most dense inflammatory cell infiltration pituitary cells contained large lysosomal bodies fusing with secretory granules (Fig. 1), as well as increased numbers of swollen mitochondria, indicating oncocytic transformation (Fig. 2).

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Correlation Between Cellular Functions and Morphological Changes of Human Trophoblast in Vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116620 ◽

1975 ◽

Vol 33 ◽

pp. 600-601

Author(s):

John C. Garancis ◽

Robert O. Hussa ◽

Michael T. Story ◽

Donald Yorde ◽

Roland A. Pattillo

Keyword(s):

Electron Microscopy ◽

Cellular Proliferation ◽

Morphological Changes ◽

Culture Fluid ◽

Cellular Functions ◽

Human Trophoblast ◽

Transmission Electron ◽

Marked Activity ◽

Malignant Trophoblast

Human malignant trophoblast cells in continuous culture were incubated for 3 days in medium containing 1 mM N6-O2'-dibutyryl cyclic adenosine 3':5'-monophosphate (dibutyryl cyclic AMP) and 1 mM theophylline. The culture fluid was replenished daily. Stimulated cultures secreted many times more chorionic gonadotropin and estrogens than did control cultures in the absence of increased cellular proliferation. Scanning electron microscopy revealed remarkable surface changes of stimulated cells. Control cells (not stimulated) were smooth or provided with varying numbers of microvilli (Fig. 1). The latter, usually, were short and thin. The surface features of stimulated cells were considerably different. There was marked increase of microvilli which appeared elongated and thick. Many cells were covered with confluent polypoid projections (Fig. 2). Transmission electron microscopy demonstrated marked activity of cytoplasmic organelles. Mitochondria were increased in number and size; some giant forms with numerous cristae were observed.

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Ethosomes and Transethosomes for Mangiferin Transdermal Delivery

Antioxidants ◽

10.3390/antiox10050768 ◽

2021 ◽

Vol 10 (5) ◽

pp. 768

Author(s):

Maddalena Sguizzato ◽

Francesca Ferrara ◽

Supandeep Singh Hallan ◽

Anna Baldisserotto ◽

Markus Drechsler ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Radical Scavenging ◽

Human Keratinocytes ◽

Antioxidant Response ◽

Correlation Spectroscopy ◽

Inflammatory Status ◽

Transmission Electron ◽

Anti Inflammatory

Mangiferin is a natural glucosyl xanthone with antioxidant and anti-inflammatory activity, making it suitable for protection against cutaneous diseases. In this study ethosomes and transethosomes were designed as topical delivery systems for mangiferin. A preformulation study was conducted using different surfactants in association with phosphatidylcholine. Vesicle dimensional distribution was monitored by photon correlation spectroscopy, while antioxidant capacity and cytotoxicity were respectively assessed by free radical scavenging analysis and MTT on HaCaT keratinocytes. Selected nanosystems were further investigated by cryogenic transmission electron microscopy, while mangiferin entrapment capacity was evaluated by ultracentrifugation and HPLC. The diffusion kinetics of mangiferin from ethosomes and transethosomes evaluated by Franz cell was faster in the case of transethosomes. The suitability of mangiferin-containing nanovesicles in the treatment of skin disorders related to pollutants was investigated, evaluating, in vitro, the antioxidant and anti-inflammatory effect of ethosomes and transethosomes on human keratinocytes exposed to cigarette smoke as an oxidative and inflammatory challenger. The ability to induce an antioxidant response (HO-1) and anti-inflammatory status (IL-6 and NF-kB) was determined by RT-PCR and immunofluorescence. The data demonstrated the effectiveness of mangiferin loaded in nanosystems to protect cells from damage. Finally, to gain insight into the keratinocytes’ uptake of ethosome and transethosome, transmission electron microscopy analyses were conducted, showing that both nanosystems were able to pass intact within the cells.

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Facile synthesis of Au/ZnO/Ag nanoparticles using Glechoma hederacea L. extract, and their activity against leukemia

Biomedical Microdevices ◽

10.1007/s10544-021-00557-0 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Renata Dobrucka ◽

Aleksandra Romaniuk-Drapała ◽

Mariusz Kaczmarek

Keyword(s):

Electron Microscopy ◽

Ag Nanoparticles ◽

Mononuclear Cells ◽

Leukemia Cell ◽

Leukemia Cell Line ◽

Mtt Test ◽

Transmission Electron ◽

Almost All ◽

Glechoma Hederacea

AbstractMetal combinations have been attracting the attention of scientists for some time. They usually exhibit new characteristics that are different from the ones possessed by their components. In this work, Au/ZnO/Ag nanoparticles were synthesized biologically using Glechoma hederacea L. extract. The synthesized Au/ZnO/Ag nanoparticles were characterized by UV-Vis, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), and Atomic Force Microscopy (AFM). The microscopic methods confirmed the presence of spherical nanoparticles of 50–70 nm. The influence of biologically synthesized Au/ZnO/Ag nanoparticles on the vitality of human cells was evaluated in vitro with the use of established human Acute T Cell Leukemia cell line, Jurkat (ATCC® TIB-152™), as well as mononuclear cells isolated from peripheral blood (PBMC) of voluntary donors. Cell survival and the half-maximal inhibitory concentration index (IC50) were analyzed by the MTT test. The studies showed that the total loss of cell viability occurred at the Au/ZnO/Ag nanoparticle concentration range of 10 µmol–50 µmol. The use of Au/ZnO/Ag nanoparticles at the concentration of 100 µmol eliminated almost all living cells from the culture in 24h. The above observation confirms the result obtained during the MTT test.

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