scholarly journals The Natural History of Uterine Leiomyomas: Light and Electron Microscopic Studies of Fibroid Phases, Interstitial Ischemia, Inanosis, and Reclamation

2013 ◽  
Vol 2013 ◽  
pp. 1-20 ◽  
Author(s):  
Gordon P. Flake ◽  
Alicia B. Moore ◽  
Deloris Sutton ◽  
Grace E. Kissling ◽  
John Horton ◽  
...  
Keyword(s):  
Cell Death ◽  
Uterine Leiomyomas ◽  
Electron Microscopic ◽  
Nutritional Deprivation ◽  
Limited Life ◽  
Microscopic Studies ◽  
History Of ◽  
End Stage ◽  
Dying Cells ◽  
Phagocytic Reaction

We propose, and offer evidence to support, the concept that many uterine leiomyomas pursue a self-limited life cycle. This cycle can be arbitrarily divided on the basis of morphologic assessment of the collagen content into 4 phases: (1) proliferation, (2) proliferation and synthesis of collagen, (3) proliferation, synthesis of collagen, and early senescence, and (4) involution. Involution occurs as a result of both vascular and interstitial ischemia. Interstitial ischemia is the consequence of the excessive elaboration of collagen, resulting in reduced microvascular density, increased distance between myocytes and capillaries, nutritional deprivation, and myocyte atrophy. The end stage of this process is an involuted tumor with a predominance of collagen, little to no proliferative activity, myocyte atrophy, and myocyte cell death. Since many of the dying cells exhibit light microscopic and ultrastructural features that appear distinct from either necrosis or apoptosis, we refer to this process as inanosis, because it appears that nutritional deprivation, or inanition, is the underlying cause of cell death. The disposal of myocytes dying by inanosis also differs in that there is no phagocytic reaction, but rather an apparent dissolution of the cell, which might be viewed as a process of reclamation as the molecular contents are reclaimed and recycled.

scholarly journals Genes required for the engulfment of cell corpses during programmed cell death in Caenorhabditis elegans.

Genetics ◽  
1991 ◽  
Vol 129 (1) ◽  
pp. 79-94 ◽  
Author(s):  
R E Ellis ◽  
D M Jacobson ◽  
H R Horvitz
Keyword(s):  
Cell Death ◽  
Caenorhabditis Elegans ◽  
Programmed Cell Death ◽  
Nematode Caenorhabditis Elegans ◽  
Electron Microscopic ◽  
New Genes ◽  
Microscopic Studies ◽  
A Cell ◽  
Cell Corpse ◽  
Dying Cells

Abstract After programmed cell death, a cell corpse is engulfed and quickly degraded by a neighboring cell. For degradation to occur, engulfing cells must recognize, phagocytose and digest the corpses of dying cells. Previously, three genes were known to be involved in eliminating cell corpses in the nematode Caenorhabditis elegans: ced-1, ced-2 and nuc-1. We have identified five new genes that play a role in this process: ced-5, ced-6, ced-7, ced-8 and ced-10. Electron microscopic studies reveal that mutations in each of these genes prevent engulfment, indicating that these genes are needed either for the recognition of corpses by other cells or for the initiation of phagocytosis. Based upon our study of double mutants, these genes can be divided into two sets. Animals with mutations in only one of these sets of genes have relatively few unengulfed cell corpses. By contrast, animals with mutations in both sets of genes have many unengulfed corpses. These observations suggest that these two sets of genes are involved in distinct and partially redundant processes that act in the engulfment of cell corpses.

scholarly journals Aziridine-2,3-Dicarboxylate-Based Cysteine Cathepsin Inhibitors Induce Cell Death in Leishmania major Associated with Accumulation of Debris in Autophagy-Related Lysosome-Like Vacuoles

2010 ◽  
Vol 54 (12) ◽  
pp. 5028-5041 ◽  
Author(s):  
Uta Schurigt ◽  
Caroline Schad ◽  
Christin Glowa ◽  
Ulrike Baum ◽  
Katja Thomale ◽  
...  
Keyword(s):  
Cell Death ◽  
Leishmania Major ◽  
Cysteine Proteinase ◽  
Membrane Integrity ◽  
New Drugs ◽  
Host Cells ◽  
Electron Microscopic ◽  
Cysteine Cathepsins ◽  
Cysteine Cathepsin ◽  
Microscopic Studies

ABSTRACT The papain-like cysteine cathepsins expressed by Leishmania play a key role in the life cycle of these parasites, turning them into attractive targets for the development of new drugs. We previously demonstrated that two compounds of a series of peptidomimetic aziridine-2,3-dicarboxylate [Azi(OBn)2]-based inhibitors, Boc-(S)-Leu-(R)-Pro-(S,S)-Azi(OBn)2 (compound 13b) and Boc-(R)-Leu-(S)-Pro-(S,S)-Azi(OBn)2 (compound 13e), reduced the growth and viability of Leishmania major and the infection rate of macrophages while not showing cytotoxicity against host cells. In the present study, we characterized the mode of action of inhibitors 13b and 13e in L. major. Both compounds targeted leishmanial cathepsin B-like cysteine cathepsin cysteine proteinase C, as shown by fluorescence proteinase activity assays and active-site labeling with biotin-tagged inhibitors. Furthermore, compounds 13b and 13e were potent inducers of cell death in promastigotes, characterized by cell shrinkage, reduction of mitochondrial transmembrane potential, and increased DNA fragmentation. Transmission electron microscopic studies revealed the enrichment of undigested debris in lysosome-like organelles participating in micro- and macroautophagy-like processes. The release of digestive enzymes into the cytoplasm after rupture of membranes of lysosome-like vacuoles resulted in the significant digestion of intracellular compartments. However, the plasma membrane integrity of compound-treated promastigotes was maintained for several hours. Taken together, our results suggest that the induction of cell death in Leishmania by cysteine cathepsin inhibitors 13b and 13e is different from mammalian apoptosis and is caused by incomplete digestion in autophagy-related lysosome-like vacuoles.

scholarly journals Pollen morphology of selected taxa of Ehretiaceae from Western Ghats, India.

2018 ◽  
Vol 7 (11) ◽  
pp. 2446
Author(s):  
Amalaurpava Mary Michael ◽  
Vijay Gopal Gumma
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Western Ghat ◽  
Electron Microscopic ◽  
History Of Vegetation ◽  
Microscopic Studies ◽  
Reserve Forest ◽  
History Of ◽  
Phylogenetic Origin ◽  
Scanning Electron

Pollen Morphology is an important tool in the identification of a genera. Data on pollen morphology is used as a reference in other fields of palynology like allergic studies, melissopalynology, tracing the history of vegetation, genetic and evolutionary studies, climate change studies etc. Pollen morphology of two genera of Ehretiaceae family is studied using Scanning electron microscope. Palynological contributions are still fragmentary in the family Ehretiaceae of southern India. Ehretia pubescens Benth is a small tree belonging to Ehretiaceae family located at the foothill of Chamundi hill reserve forest which is a part of Western ghat near Mysuru and Cormona retusa (Vahl) Masam is a shrub found 3400ft above on top of Chamundi Hill. Pollen grains were acetolyzed and Scanning Electron Microscopic studies conducted to obtain data on pollen morphology. The study is conducted to assess the taxonomic significance of pollen morphology in relation to their phylogenetic origin of the two genera of Ehretiaceae in the region. The palynological evidence shows Ehretia pubescens with tri-zonocolporate and heterocolpate pollen grains and Cormona retusa with tricolpate pollen grain without the pseudocolpi. Both genera have foveolate tectum. Palynological data indicate that these two naturalized taxa ie. Ehretia pubescens and Cormona retusa belong to two different lineage of Ehretia and can be identified by their pollen morphology. Diversity in the pollen characters points towards the eurypalynous nature in Ehretiaceae.

Proliferative glomerulonephritis with monoclonal immunoglobulin deposits: a nephrologist perspective

2019 ◽  
Author(s):  
Frank Bridoux ◽  
Vincent Javaugue ◽  
Samih H Nasr ◽  
Nelson Leung
Keyword(s):  
Cell Clone ◽  
Early Recurrence ◽  
Proliferative Glomerulonephritis ◽  
Monoclonal Immunoglobulin ◽  
Electron Microscopic ◽  
Nephritic Syndrome ◽  
Microscopic Studies ◽  
Immunoglobulin Deposits ◽  
Stage Renal Disease ◽  
End Stage

AbstractProliferative glomerulonephritis (GN) with monoclonal immunoglobulin deposits (PGNMIDs) is a recently described entity among the spectrum of monoclonal gammopathy of renal significance (MGRS). The disease is renal limited and manifests with chronic glomerular disease, altered renal function and albuminuria, sometimes in the nephrotic range. Acute nephritic syndrome is rare. PGNMID occurs mostly in the sixth decade, but it may affect young adults. Histologically, PGNMID is characterized predominantly by membranoproliferative GN and less frequently by diffuse endocapillary GN, mesangioproliferative GN or atypical membranous GN. Immunofluorescence and electron microscopic studies are the cornerstone of diagnosis, showing granular deposits involving glomeruli only, and composed of monotypic immunoglobulin G (IgG), with a single heavy chain subclass (most commonly IgG3) and light chain (LC) restriction (usually κ), admixed with complement deposits. PGNMID variants with monotypic LC-only, IgA or IgM deposits are uncommon. Ultrastructurally, deposits are amorphous with predominant subendothelial and mesangial distribution. PGNMID should be distinguished from type 1 cryoglobulinemic GN and immunotactoid GN, which share some common pathological features. Contrary to other MGRS lesions, the rate of detection of the nephrotoxic monoclonal Ig in the serum or urine, and of an abnormal bone marrow B-cell clone, is only ∼30%. Renal prognosis is poor, with progression to end-stage renal disease in 25% of patients within 30 months and frequent early recurrence on the renal allograft. The pathophysiology of PGNMID is unclear and its treatment remains challenging. However, recent studies indicate that clone-targeted chemotherapy may significantly improve renal outcomes, opening future perspectives for the management of this rare disease.

Tubular intranuclear inclusions in a patient with methotrexate-associated pulmonary fibrosis

1983 ◽  
Vol 41 ◽  
pp. 796-797
Author(s):  
W.T. Gunning ◽  
P.J. Goldblatt
Keyword(s):  
Interstitial Fibrosis ◽  
Inflammatory Cells ◽  
Giant Cells ◽  
Skin Condition ◽  
Intermittent Fever ◽  
Electron Microscopic ◽  
Type Ii Pneumocytes ◽  
Microscopic Evaluation ◽  
Microscopic Studies ◽  
History Of

A forty-six year old male, who had received methotrexate therapy for the past year for psoriasis of twenty years' duration, presented with a cough which had persisted for two to three months. There was a two year history of dyspnea upon exertion as well as intermittent fever, chills and sweats. The methotrexate treatment did not improve the skin condition and, because there was evidence of hepatic toxicity, the drug was discontinued. Radiological examination of the chest revealed diffuse bilateral interstitial fibrosis with extensive changes; a subseguent lung biopsy was obtained. Light microscopic evaluation demonstrated marked interstitial fibrosis, chronic inflammation, thickening of the alveolar septa, proliferation of alveolar macrophages, occasional fibrin deposits and multinucleated giant cells.Electron microscopic studies revealed massive fibrosis with a mixed population of infiltrating inflammatory cells. Some alveolar spaces were lined by metaplastic cuboidal epithelial cells, and in numerous residual type II pneumocytes, aggregates of branching tubules lined by trilaminar membranes were identified within the nucleus.

scholarly journals A holistic insight of mycobacteriophage induced changes in mycobacterial cells

2021 ◽  
Author(s):  
Fatema Calcuttawala ◽  
Rahul Shaw ◽  
Arpita Sarbajna ◽  
Moumita Dutta ◽  
Saptarshi Sinha ◽  
...  
Keyword(s):  
Cell Death ◽  
Electron Microscopic Examination ◽  
Cellular Level ◽  
Electron Microscopic ◽  
Major Mechanism ◽  
Membrane Pores ◽  
Transmission Electron ◽  
Before And After ◽  
Microscopic Studies ◽  
Induced Changes

Mycobacteriophages are phages that interact with mycobacteria resulting in their killing. Although lysis is the major mechanism by which mycobacteriophages cause cell death, other mechanisms may also be involved. The present study was in i tiated with the objective of investigating the changes that take place at the cellular level following the infection of mycobacterial cells by phage D29.  To investigate th is issue, we took recourse to performing immunofluorescence and electron microscopic studies . Transmission electron microscopic examination reveal ed the adsorption of phages on to the surface of mycobacteria , f ollowing which penetration of the tail through the thick mycol o ic acid layer was seen . At later time points discrete populations of cells at different stages of lysis we re observed , which comprised of complete ly lys ed cells , in which the cells were fragmented and those at the early onset stage exhibited formation of membrane pores through which the phages and intracellular contents were released.   SEM results also indicate d that phages may come out through the entire surface of the cell, or alternatively through gaps in the surface. In some of the images we observed structures that apparently resembled membrane blebs which are normally encountered when cells undergo programmed cell death (PCD). In addition, we observed significant increase in DNA fragmentation as well as membrane depolarization, which are also indicative of occurrence of PCD. As several bacterial PCD pathways are mediated by the toxin-antitoxin (TA) modules, the expression profile of all the TA systems was examined before and after phage infection. Apart from specifically addressing the issue of PCD in mycobacteriophage infected cells, this investigation has led to the development of facile tools necessary for investigating mycobacteriophage-mycobacteria interactions by means of microscopic methods.

Rhinosporidiosis: immunohistochemical and electron microscopic studies

1994 ◽  
Vol 108 (12) ◽  
pp. 1048-1054 ◽  
Author(s):  
Bahram Azadeh ◽  
Nina Baghoumian ◽  
Osama T. El-Bakri
Keyword(s):  
Electron Microscopy ◽  
Late Stage ◽  
Immigrant Workers ◽  
Electron Microscopic ◽  
Male Immigrant ◽  
Microscopic Studies ◽  
End Stage ◽  
Indian Male

AbstractSixteen biopsies of rhinosporidiosis (15 nasal and one conjunctival) from 16 Southern Indian male immigrant workers showed mucosal lymphoplasmacellular infiltrates together with transepithelial elimination of nodular bodies and destruction of some late stage nodular bodies in histiocytic granulomata with central neutrophilic microabscesses. Early nodular bodies were immunohistochemically positive for alpha1-AT, alpha1-ACT, CEA, S100, fibronectin, amyloid-p-component, IgG, IgA, CIq and C3. Electron microscopy showed organizedconcentric lamellated bodies in early nodular bodies and not in end-stage nodular bodies which contained mostly amorphous electron dense materials. Structures formerly regarded as ‘sporangia’ and ‘spores’ are believed to be lysosomal bodies loaded with indigestible residues to be cleared via transepithelial elimination or segregated/destroyed by secondary immune/granulomatous responses.

Vascular regression during the formation of the free digits in the avian limb bud: a comparative study in chick and duck embryos

Development ◽  
1985 ◽  
Vol 85 (1) ◽  
pp. 239-250
Author(s):  
J. M. Hurle ◽  
E. Colvee ◽  
M. A. Fernandez-Teran
Keyword(s):  
Cell Death ◽  
Blood Vessels ◽  
Mesenchymal Cell ◽  
Limb Bud ◽  
Death Process ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Cell Death Process

The pattern and structure of the blood vessels of the interdigital spaces of the leg bud have been studied by means of Indian ink injections and transmission electron microscopy in the chick and duck embryos. The results show that in the chick the interdigital necrotic process responsible for the freeing of the digits is followed by regression of the blood vessels. In the webbed foot of the duck, the interdigital necrotic processes are not followed by vascular regression. Transmission electron microscopic studies show that both in the chick and in the duck, interdigital blood vessels are immature structures lacking basal lamina. Dead cells of presumably endothelial origin were detected in the lumen of the regressing blood vessels of the chick but not in the duck. However, the intensity of this cell death process does not appear to be high enough to account by itself for the disappearance of the interdigital blood vessels. The possible relationships between interdigital mesenchymal cell death and vascular regression are discussed.

Electron microscopic studies on ultrathin frozen sections of lactating mouse mammary gland

1978 ◽  
Vol 36 (2) ◽  
pp. 46-47
Author(s):  
Jan Zarzycki ◽  
Joseph Szroeder
Keyword(s):  
Mammary Gland ◽  
Protein Denaturation ◽  
Chemical Constituents ◽  
Freeze Substitution ◽  
Electron Microscopic Examination ◽  
Mouse Mammary Gland ◽  
Electron Microscopic ◽  
Preparation Methods ◽  
Microscopic Studies ◽  
Ultrathin Frozen Sections

The mammary gland ultrastructure in various functional states is the object of our investigations. The material prepared for electron microscopic examination by the conventional chemical methods has several limitations, the most important are the protein denaturation processes and the loss of large amounts of chemical constituents from the cells. In relevance to this,one can't be sure about a degree the observed images are adequate to the realy ultrastructure of a living cell. To avoid the disadvantages of the chemical preparation methods,some autors worked out alternative physical methods based on tissue freezing / freeze-drying, freeze-substitution, freeze-eatching techniqs/; actually the technique of cryoultraraicrotomy,i,e.cutting ultrathin sections from deep frozen specimens is assented as a complete alternative method. According to the limitations of the routine plastic embbeding methods we were interested to analize the mammary gland ultrastructure during lactation by the cryoultramicrotomy method.

Early Development of Drug-Induced Hepatic Necrosis

1971 ◽  
Vol 29 ◽  
pp. 576-577
Author(s):  
F. G. Zaki ◽  
E. Detzi ◽  
C. H. Keysser
Keyword(s):  
Early Development ◽  
Hepatic Necrosis ◽  
Screening Tests ◽  
Dense Matrix ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Drug Induced ◽  
Hepatocellular Damage ◽  
Sprague Dawley Rats ◽  
Microscopic Studies

This study represents the first in a series of investigations carried out to elucidate the mechanism(s) of early hepatocellular damage induced by drugs and other related compounds. During screening tests of CNS-active compounds in rats, it has been found that daily oral administration of one of these compounds at a dose level of 40 mg. per kg. of body weight induced diffuse massive hepatic necrosis within 7 weeks in Charles River Sprague Dawley rats of both sexes. Partial hepatectomy enhanced the development of this peculiar type of necrosis (3 weeks instead of 7) while treatment with phenobarbital prior to the administration of the drug delayed the appearance of necrosis but did not reduce its severity.Electron microscopic studies revealed that early development of this liver injury (2 days after the administration of the drug) appeared in the form of small dark osmiophilic vesicles located around the bile canaliculi of all hepatocytes (Fig. 1). These structures differed from the regular microbodies or the pericanalicular multivesicular bodies. They first appeared regularly rounded with electron dense matrix bound with a single membrane. After one week on the drug, these vesicles appeared vacuolated and resembled autophagosomes which soon developed whorls of concentric lamellae or cisterns characteristic of lysosomes (Fig. 2). These lysosomes were found, later on, scattered all over the hepatocytes.

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