Effect of dose of estradiol and age of animals on intranuclear inclusions in mammotrophs of the Mongolian gerbil.

Intranuclear inclusions have been examined in mammotrophs of the Mongolian gerbil. No inclusions were identified in nuclei of newborn females, although inclusions were seen in the pituitary gland of young mature females. The number of inclusions in retired breeders was similar to that in young females. Estradiol benzoate increased the number of inclusions, although 10 mug/day for 5 or 14 days induced more inclusions than 5 or 100 mug for 14 days; significantly fewer inclusions were seen with the higher dose (2.81 +/- 0.10 inclusions per field for 10 mug and 2.19 +/- 0.01 inclusions for 100 mug). Significantly fewer inclusions were present at 3 and 4 weeks. The reduced number of inclusions may be attributable at least in part to cellular hypertrophy of mammotrophs which was especially prominent. Vacuolar inclusions predominated at 3 and 4 weeks and there were fewer membranous types than at previous times.     

Effect of partial thyroidectomy, propylthiouracil or thyroxine on estrogen-induced intranuclear inclusions in mammotrophs of the Mongolian gerbil

Partial thyroidectomy caused a significant increase in the number of intranuclear inclusions per field (2-83 +/- 0-10 inclusions as compared with 0-15 +/- 0-03 inclusions for sham-controls). The inclusions occurred exclusively within mammotrophs. Thyrotrophs were stimulated: an increased cell size, numerous secretory granules, an enlarged Golgi apparatus and hypertrophic rough endoplasmic reticulum. Propylthiouracil caused similar ultrastructural changes although sighificantly fewer inclusions were observed (0-64 +/- 0-06 inclusions). Suppression of thyroid function with thyroxine produced no change in the number of inclusions (0-17 +/- 0-03 inclusions) although when combined with estrogen there were significantly fewer inclusions (1-62 +/- 0-07) when compared to estrogen alone (2-69 +/- 0-09). Intranuclear inclusions appear to be a unique reaction of mammotrophs to cellular hyperfunction in the Mongolian gerbil.     

Electron-microscopic study of the development of an equine adenovirus in cultured fetal equine kidney cells

Sequential changes induced by an equine adenovirus in cultured fetal equine kidney cells were studied by electron microscopy. The first morphological change was the appearance of type I inclusions. These inclusions developed to type II inclusions which appeared as ring forms. Type III inclusions were formed within the central part of type II inclusions and finally filled up most of the nuclear space. As the infection proceeded, type IV inclusions which appeared as dense dark-staining spheres were formed at the center of the type III inclusions and also inside the cytoplasm. These dark-staining spheres developed and their center was filed with light-staining material and virus particles which eventually resulted in the formation of type V inclusions. Autoradiography study showed that types I, II, and III were composed of nucleoprotein and type IV was composed of protein.     

CYTOPLASMIC DIFFERENCES IN T-TYPE CYTOPLASMIC MALE-STERILE CORN AND ITS MAINTAINER

Edwardson , John R. (U. Florida, Gainesville.) Cytoplasmic differences in T-type cytoplasmic male-sterile corn and its maintainer. Amer. Jour. Bot. 49 (2) : 184–187. Illus. 1962.—Differences in inclusions in sections of T-type male-sterile and maintainer corn were found with electron microscopy. Some male-sterile root tip cells contain dense inclusions ca. 50–60 mμ dia. These inclusions are always associated with areas of dense cytoplasm, while no such inclusions or dense cytoplasmic areas occur in maintainer material. The majority of maintainer tapetal cells contain inclusions ca. 46–52 mμ dia.; the majority of male-sterile tapetal cells contain inclusions ca. 58–64 mμ dia. Well-defined membranes always enclose the inclusions in maintainer material; indistinct membranes are occasionally associated with inclusions in sterile material.     

Characterization of intracytoplasmic hydrocarbon inclusions from the hydrocarbon-oxidizing Acinetobacter species HO1-N.

The ultrastructure of Acinetobacter sp. strain HO1-N grown on hydrocarbon and nonhydrocarbon substrates was compared using thin sections and freeze-etching. Hydrocarbon-grown cells were characterized by the presence of intracytoplasmic membrane-bound hexadecane inclusions. This membrane did not exhibit a typical unit membrane structure but appeared as a monolayer. The freeze-etch technique revealed the internal structure of the hexadecane inclusions and provided evidence for the presence of a smooth-surfaced limiting membrane. Freeze-etching also revealed intracytoplasmic membranes in the hexadecane-grown cells. These ultrastructural modifications were not present in nonhydrocarbon-grown cells. The hexadecane inclusions were isolated from Acinetobacter. Negative-staining of the inclusions revealed electron-transparent vesicles approximating the size of the inclusions seen in whole cells. Freeze-etching of the purified inclusions revealed membrane-bound vesicles. The purified inclusions exhibited a relatively high value of lipid phosphorus to protein. The lipid composition and the electrophoretic banding pattern of the inclusions on sodium dodecyl sulfate-polyacrylamide gels were determined and compared with other membrane fractions (outer membrane and cytoplasmic membrane) previously isolated from this organism.     

Inclusion bodies in pinealocytes of the cotton rat (Sigmodon hispidus)

Pinealocytes of the cotton rat (Sigmodon hispidus) often contain large (2-6 micron diameter) intracytoplasmic inclusions, the function of which is not known. These inclusions may represent nucleolus-like bodies, mineral deposits, secretory products or viral inclusions. In this study these inclusions were classified as type A, B or C inclusions based on the amount of electron-dense material interspersed within the finely granular material comprising the bulk of these inclusions. Each type of inclusion was analyzed by X-ray microanalysis and enzymatic proteinaceous digestion. X-ray microanalysis of these inclusions differed both quantitatively and semiquantitatively from that of human or gerbil pineal concretions, the latter two of which are extracellular deposits. Pronase, a proteolytic enzyme, digested the electron-dense material only after longer times of tissue exposure to this enzyme in contrast to the easily digested, finely granular matrix-like material of these inclusions. Such intrapinealocytic inclusions have only been observed in the cotton rat. Their functional significance remains unknown.     

The effect of dihydrotestosterone in combination with ovariectomy on intranuclear inclusions in mammotrophs of the Mongolian gerbil

Intranuclear vacuoles and membranes have been observed in mammotrophs of female Mongolian gerbils. Testosterone injection increases the number of cells containing inclusions (1·77±008 inclusions per field in testosterone-injected animals and 0·38±0·05 inclusions per field in controls). Testosterone may well be converted to some other compound which in turn induces the inclusions. Ovariectomy presumably prevented such a conversion inasmuch as testosterone was ineffective in increasing the number of inclusions in ovariectomized gerbils. Neither did the injection of dihydrotestosterone, the biologically active form of testosterone in some organs, increase the number of cells containing intranuclear inclusions.     

斜带髭鲷外周血嗜中性粒细胞核内包涵体的超微结构

目的在对斜带髭鲷（Hapalogenys nitens）外周血细胞结构进行透射电镜观察时发现嗜中性粒细胞存在大量的核内包涵体,系统研究了这些核内包涵体的超微结构,以探讨其来源和形成过程。方法应用电镜技术对这些核内包涵体的超微结构进行研究。结果斜带髭鲷外周血嗜中性粒细胞的核内包涵体可分为假包涵体和真包涵体两种类型,包涵体中的内含物来自胞质。胞核首先是以核膜内陷的方式将胞质及其各种有形成分包绕进核内而在核质外层形成具有双层膜包裹的典型假包涵体,随后假包涵体双层膜降解消失而转化成无被膜包裹的真包涵体,即核内糖原包涵体。结论假包涵体是形成真包涵体的开始阶段。随着假包涵体向真包涵体的转变,包涵体内含物的组成及其超微结构也出现了显著变化。     

Mode de formation des inclusions lamellaires dans le poumon embryonnaire de poulet

Résumé Les pneumocytes granuleux, qui constituent l'un des principaux types cellulaires de l'épithélium pulmonaire, sont caractérisés par la présence de volumineuses inclusions osmiophiles lamellaires.Nous avons étudié l'apparition et l'origine de ces inclusions dans l'épithélium du poumon embryonnaire de Poulet, en l'examinant à différents stades du développement.Les premières inclusions lamellaires apparaissent dans le poumon de l'embryon de 16 jours. A ce stade, quelques lamelles concentriques entourent une zône centrale amorphe étendue; la périphérie des inclusions contient toujours de petites structures granulaires. Les jours suivants le nombre de cellules contenant des inclusions lamellaires augmente rapidement; en même temps, les lamelles deviennent plus nombreuses. A 19 jours, les inclusions lamellaires ont un aspect semblable à celui qu'elles ont dans les poumons d'animaux adultes.Dès l'apparition des ébauches pulmonaires, à 2 1/2 jours d'incubation, les cellules épithéliales contiennent des inclusions typiques: les inclusions granulaires. Ces organites sont caractérisés par un centre granulaire, qu'entouré un système membranaire. Ce système, simple chez le jeune embryon, évolue ensuite en se compliquant; chez l'embryon de 16 jours, il s'enroule en plusieurs couches autour de la masse centrale. Au moment où les premières inclusions lamellaires apparaissent, le nombre des inclusions granulaires augmente rapidement; on les trouve souvent étroitement associées à des vacuoles lipidiques.L'analyse des relations entre inclusions lamellaires, inclusions granulaires et vacuoles lipidiques suggère que l'inclusion lamellaire résulte de la collaboration entre une vacuole lipidique et plusieurs inclusions granulaires.

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Differentiation of lamellar inclusions in the chick embryonic lung

Summary The granular pneumocytes, one of the main cellular types of the lung epithelium, are characterized by the presence of large osmiophilic lamellar inclusions. The appearance and origin of these inclusions has been studied in the epithelium of chick embryonic lung at different developmental stages.Lamellar inclusions are first seen in the lung of 16 day old embryos. At this stage, few concentric lamellae surround a large amorphous center; the periphery of the inclusions always contains small granular structures. In the following days, the number of cells containing these lamellar inclusions increases rapidly, while their lamellae progressively become more numerous. In 19 day old embryos, the lamellar inclusions are similar to those in the lungs of adult animals.From the earliest formation of the bronchial primordia, their epithelial cells contain a number of typical granular inclusions. These organelles are characterized by a granular center, enclosed in a membranous system. This structure becomes more complex as the embryo develops; in the 16 day old embryo, the multilayered membranous system coils around the granular center. At the time when lamellar inclusions first appear, granular inclusions increase rapidly in number and are often found in close association with lipidic vacuoles.The relationships between lamellar inclusions, granular inclusions and lipidic vacuoles are discussed. The evidence suggests that a lamellar inclusion arises from the cooperation of several granular inclusions and a lipidic vacuole.

     

Fine Structure of Cellular Inclusions in Pericarp Cells of Polysiphonia deusta (Ceramiales, Rhodophyta)

The ultrastructure of cytoplasmic inclusions in pericarp cells(cystocarpic plant) of Polysiphonia deusta shows five structuraltypes of inclusions; (1) membrane-bounded crystalloid inclusionsthat are composed of tetragonally packed fibrils, each 8 nmdiam., spaced 17.5 nm between centres; (2) membrane-boundedcrystalloid-like inclusions with incomplete structure; (3) unboundedcrystalline body without a distinct crystal lattice pattern;(4) membrane-limited fibrillar inclusions; (5) fibrillogranularstructure. The membranes of the first two inclusions were coveredwith ribosomes and seem to be elements of endoplasmic reticulum. Polysiphonia deusta, pericarp cells, cellular inclusions     

Elemental composition of bacterial metachromatic inclusions determined by electron microprobe X-ray analysis.

Electron microscopy and microprobe X-ray analysis were used to study metachromatic inclusions of Spirillum itersonii , Corynebacterium diphtheriae, and Micrococcus luteus. In situ metachromatic inclusions were electron dense and contained phosphorus and divalent cations. Metachromatic inclusions isolated by anion-exchange column chromatography and by isoosmolar Metrizamide density gradient centrifugation were similar in composition to in situ inclusions.     

Cellular cholesteryl ester clearance. Relationship to the physical state of cholesteryl ester inclusions

The hypothesis that clearance of cellular cholesteryl ester deposits may be a function of the physical state of the stored lipid has been investigated. Cultured rat hepatoma cells were induced to store cholesteryl ester in either anisotropic inclusions by exposure to free cholesterol-rich phospholipid dispersions or isotropic inclusions by exposure to identical dispersions supplemented with oleic acid. Differential scanning calorimetry demonstrated an order/disorder transition at 43 degrees C for cholesteryl esters stored in anisotropic inclusions; the enthalpy of this transition was consistent with a smectic liquid crystalline to liquid transition. Lipids in cells with isotropic inclusions displayed no order/disorder transitions over the range 20-80 degrees C, indicating that the lipids are in a liquid state. The presence of oleic acid did not influence the mass of cholesteryl ester stored but increased the amount of stored triglyceride. Fatty acyl compositions of the cholesteryl esters were different under the two loading conditions; in particular, there was 38% cholesteryl oleate in anisotropic inclusions and 65% cholesteryl oleate in isotropic inclusions. Kinetics of cholesteryl ester clearance from cells with either anisotropic or isotropic inclusions were studied during a 12-h exposure to acceptors of free cholesterol. In both cases, cholesteryl ester clearance is essentially linear over 12 h and is directly proportional to the initial content of cholesteryl ester. However, the fraction of initial content of cholesteryl ester cleared in 12 h is 0.17 +/- 0.05 for cells with anisotropic inclusions and 0.34 +/- 0.09 for cells with isotropic inclusions. Our data demonstrate that the more rapid clearance of cholesteryl ester by cells with isotropic inclusions can be correlated with the physical state of the cholesteryl ester.     

Shape variation of bilayer membrane daughter vesicles induced by anisotropic membrane inclusions

A theoretical model of a two-component bilayer membrane was used in order to describe the influence of anisotropic membrane inclusions on shapes of membrane daughter micro and nano vesicles. It was shown that for weakly anisotropic inclusions the stable vesicle shapes are only slightly out-of-round. In contrast, for strongly anisotropic inclusions the stable vesicle shapes may significantly differ from spheres, i.e. they have a flattened oblate shape at small numbers of inclusions in the membrane, and an elongated cigar-like prolate shape at high numbers of inclusions in the vesicle membrane.     

Intranuclear inclusions in urinary cytology

Twenty-one urinary cytology specimens from 16 patients showed red intranuclear inclusion bodies. The literature pertinent to these inclusions mainly suggests that lead poisoning is a cause for such inclusions. Histories were reviewed for possible causes, particularly lead poisoning, associated medications, associated illness or relationship to neoplasia. The only consistent associations found were that all the patients were women over the age of 50 and that all inclusions were found in voided urine specimens. Four slides containing inclusions were stained by acid-fast methods, with negative results. The origin of these inclusions remains unknown.     

Differential morphology and composition of inclusions in the R6/2 mouse and PC12 cell models of Huntington’s disease

The histological hallmark feature of Huntington’s disease (HD) and other polyglutamine repeat diseases is the presence of intracellular inclusions. Much work has been devoted to trying to determine the relationship between inclusion formation and neuronal injury. However, little attention has been paid to the variability and characteristics of inclusions themselves. Here, we characterize the morphological and biochemical composition of inclusions in both a transgenic mouse model (R6/2 line) and an inducible cell culture model of HD (iPC12Q74). We identified several morphologically distinct kinds of inclusions in different locations (nuclei, cytoplasm and cellular processes). Ubiquitin colocalized completely with all of these inclusions in both the iPC12Q72 and R6/2 models. In the inclusions in iPC12Q74 cells, the 20S and 11S proteasome subunits colocalized variably, and the 19S subunit did not colocalize at all. In inclusions in R6/2 mouse neurons, the 20S subunit colocalized completely, but neither the 11S nor the 19S subunits colocalized at all. While the role of inclusions in the pathogenesis of HD continues to be debated, we suggest that the content and structure of inclusions vary considerably, not only from cell to cell but even within individual cells. Their role in the pathogenesis of HD is likely to depend on their location as well as their composition.     

An Electron Microscope Study of Intranuclear Inclusions in Mouse Liver and Hepatoma

An electron microscope study of intranuclear inclusions which occur in giant cells in a transplantable mouse hepatoma and in enlarged liver cells in mice fed a diet containing bentonite demonstrates that these inclusions are formed by invaginations of the nuclear envelope, and corroborates a previous histochemical study which revealed that the contents of the inclusions are of cytoplasmic origin. In the hepatoma cells the intranuclear inclusions are abundant, small, and situated close to the border of the nucleus, and there are wide openings from the cytoplasm into the invaginations whose contents include lipid droplets, ergastoplasm, and structurally normal mitochondria. In the enlarged liver cells the inclusions are fewer in number, generally much larger than those in the hepatoma, hence they extend deeper into the nucleus, and the interior is continuous with the cytoplasm through only a small opening. Some normal ergastoplasm is present within the inclusions but all other constituents are abnormal. Both normal and degenerating mitochondria occur in the cytoplasm but only degenerating ones are found within the inclusions. Both types of inclusions arise in greatly enlarged cells in which an attempt is made to maintain the normal nuclear surface/nuclear volume ratio by the development of the invaginations of the nuclear envelope.     

Inclusions in aged mitochondria

The formation of paracrystalline inclusions in mitochondria following postmortem aging in situ is further investigated. Inclusions are found to localize either in the mitochondrial intracristal space or between the inner and outer membrane. The greater majority of the inclusions are of the intracristal type. pH is not an important factor in the formation of the inclusions, since lowering the pH of the mitochondrial suspensions does not increase the number of mitochondria with inclusions. It is concluded that changes associated with aging during the prolonged preservation of the mitochondria both in situ and in in vitro experiments are probably the principal cause for the formation of the mitochondrial inclusions.     

Isolation and characterization of cytoplasmic inclusions from influenza A virus-infected cells.

Influenza A viruses induce the accumulation of electron-dense inclusions in the cytoplasm of infected cells during the latter stages of the replication cycle. Cell fractionation studies showed that these inclusions could be recovered in subcellular fractions containing ribosomes and polysomes. Isolation of these inclusions was accomplished by procedures involving RNase treatment of these fractions followed by repurification, or by fluorocarbon extraction and gradient centrifugation. Electron microscopy indicated that the isolated inclusions exhibited a major periodicity of approximately 8 nm with minor periodicities of approximately 4 nm. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the influenza virus coded nonstructural protein was the only protein component present in isolated inclusions.     

Viral DNA Synthesis In Vitro with the Inclusions Isolated from Adenovirus 12-Infected Cells

A fraction defined as the inclusions was isolated by banding in CsCl gradients from nuclei of adenovirus 12-infected KB cells. When examined by electron microscopy, the isolated inclusions were relatively homogeneous, finely granular materials of moderate electron density, possibly representing the disintegrated type II or IV inclusions. The conditions of endogenous DNA synthesis in vitro with the inclusions were determined. The product of DNA synthesis in vitro with the inclusions was mainly viral and scarcely cellular, as revealed by DNA-DNA hybridization and methylated albumin kieselgur column chromatography. However, viral DNA synthesized in vitro was smaller (18 S, 22 S) than viral DNA in virions (31 S, 34 S) in neutral and alkaline sucrose gradients. Effects of various treatment of the inclusions on the DNA-synthesizing activity showed that phospholipase C inhibited the activity efficiently. The in vitro DNA synthesis was stimulated by addition of the cytoplasmic extract from adenovirus 12-infected cells and not that from unifected cells. The analysis of the composition of the inclusions showed that the inclusions contained DNA, protein, phospholipid and a small amount of RNA and carbohydrate.