scholarly journals AN ELECTRON MICROSCOPE STUDY OF THE DEVELOPMENT OF SV40 VIRUS

1963 ◽  
Vol 17 (2) ◽  
pp. 423-441 ◽  
Author(s):  
Nicole Granboulan ◽  
P. Tournier ◽  
R. Wicker ◽  
W. Bernhard
Keyword(s):  
Electron Microscope ◽  
Close Contact ◽  
Kidney Cells ◽  
Thin Sections ◽  
Sv40 Virus ◽  
Virus Particles ◽  
The Relationship ◽  
Infectious Cycle ◽  
Number Of Cells

Kidney cells, predominantly from Cercopithecus monkeys but also from baboons, were infected in vitro with the SV40 virus. The infectious cycle was studied with the electron microscope by means of thin sections of cells fixed from 3 hours up to 11 days after infection. The frequency of virus formation and various nuclear and cytoplasmic lesions in relation to the infection are described. The virus particles appear in the nucleus in close contact with the chromatin. In a small number of cells they have been observed as early as 10 to 12 hours after infection, but most often they appear 24 to 48 hours afterward. Their mean diameter is 33 mµ. They have no membrane and are frequently arranged as crystal-like structures. In addition to the appearance of virus, one observes various lesions in the nucleoplasm and particularly in the nucleolus, which shows an early hypertrophy and produces unusual, dense condensations in contact with the nucleolonema. The importance of these nucleolar lesions and the relationship between the SV40 virus and the polyoma, common wart, and Shope papilloma viruses are discussed.

scholarly journals INTRACELLULAR FORMS OF POX VIRUSES AS SHOWN BY THE ELECTRON MICROSCOPE (VACCINIA, ECTROMELIA, MOLLUSCUM CONTAGIOSUM)

1953 ◽  
Vol 98 (2) ◽  
pp. 157-172 ◽  
Author(s):  
William H. Gaylord ◽  
Joseph L. Melnick
Keyword(s):  
Electron Microscope ◽  
Hollow Spheres ◽  
Molluscum Contagiosum ◽  
Dense Granule ◽  
Homogeneous Material ◽  
Dense Matrix ◽  
Thin Sections ◽  
Virus Particles ◽  
Typical Inclusion ◽  
Mature Virus

The intracellular development of three pox viruses has been studied with the electron microscope using thin sections of infected tissue. Cells infected with vaccinia, ectromelia, and molluscum contagiosum viruses all form developmental bodies preliminary to the production of mature virus. Developmental bodies, believed to be virus precursors, are round to oval, slightly larger than mature virus particles, less dense to electrons, and have a more varied morphology. It is suggested as a working hypothesis that the process of maturation of a virus particle takes place as follows. In the earliest form the developmental bodies appear as hollow spheres, imbedded in a very dense cytoplasmic mass constituting an inclusion body, or in a less dense matrix near the nucleus in cells without typical inclusion bodies. The spheres become filled with a homogeneous material of low electron density. A small, dense granule appears in each developmental body and grows in size at the expense of the low density material. Following growth of the granule, particles are found with the dimensions of mature virus and having complex internal structure resembling bars or dumbells. Mature virus is ovoid and very dense to electrons. An "empty" interior may be found within its thick walls.

An Inverse Relation Between Cell Density and the Number of Microvilli in Cultures of BHK 21 Hamster Fibroblasts

1970 ◽  
Vol 7 (3) ◽  
pp. 695-709
Author(s):  
C. H. O'NEILL ◽  
E. A. C. FOLLETT
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Monolayer Culture ◽  
Cell Contact ◽  
Inverse Relation ◽  
Culture Density ◽  
Microscope Technique ◽  
The Relationship ◽  
Number Of Cells ◽  
Scanning Electron

The relationship between culture density and the number of microvilli on the cell surface has been studied using BHK21 cells in established monolayer culture. The number of microvilli can be estimated quantitatively by a scanning electron-microscope technique. It can be increased by applying specific antiserum, but whether antibody is applied or not a significant number of cells regularly bear microvilli. This number is characteristic of the culture density. In sparse cultures above a certain minimum density it is relatively high, and in confluent cultures it is much reduced. These results indicate that microvilli may be inhibited by cell contact.

The relationship between milk yield, composition and tissue damage in a case of subclinical mastitis

1963 ◽  
Vol 30 (1) ◽  
pp. 23-33 ◽  
Author(s):  
R. Waite ◽  
P. S. Blackburn
Keyword(s):  
Chemical Composition ◽  
Milk Yield ◽  
Tissue Damage ◽  
Subclinical Mastitis ◽  
Bacteriological Examination ◽  
Cell Content ◽  
Upper Level ◽  
The Relationship ◽  
Number Of Cells

SummaryA chemical, cytological and bacteriological examination of the milk from each quarter of a cow suffering from subclinical mastitis, but giving 5–6 gal of milk per day, was made at weekly intervals during the first 84 days after parturition. The infection, caused by micrococcal and staphylococcal bacteria, resisted repeated treatments with various antibiotics administered via the teat canals and also intramuscularly, although in vitro the bacteria were susceptible to all the antibiotics used. The cow was slaughtered and a histological examination made of the udder in an attempt to establish the cause of the continuing infection and to assess the extent of tissue damage. Two quarters each contained large abscesses in the upper level of the udder and these could have acted as reservoirs of infection; no cause was established for the other two quarters and it can only be assumed that reinfection occurred from the two abscessed quarters.The amount of active lesions in the lobules of all the quarters was small, 1–6%, but half or more of all the lobules were involuted, although only a minority appeared to have involuted as a result of infection. In the two abscessed quarters there was extensive damage to the duct system, 23 and 31% showing lesions.When the milk contained an abnormally large number of cells the chemical composition was also abnormal, containing less lactose (and hence less solids-not-fat) and having a nitrogen distribution in which there was more blood serum albumin and globulin and less casein than usual. Cell content and chemical composition were better indicators of tissue damage than the presence of mastitis organisms. It is estimated that the solids-not-fat content of the milk of the whole udder as a result of the infections was considerably lower than it would otherwise have been (8·0 instead of 8·8%) and that the daily loss in milk yield was about 9 lb.

scholarly journals An Electron Microscope Study of Polyoma Virus in Hamster Kidney

1960 ◽  
Vol 7 (4) ◽  
pp. 753-760 ◽  
Author(s):  
Allan F. Howatson ◽  
June D. Almeida
Keyword(s):  
Electron Microscope ◽  
Stromal Cells ◽  
Polyoma Virus ◽  
Tubular Structures ◽  
Cytoplasmic Inclusions ◽  
Virus Particles ◽  
Large Numbers ◽  
Mouse Cells ◽  
Newborn Animals

Electron microscope studies were made of hamster kidneys taken at daily intervals after injection of a variant of polyoma virus into newborn animals. Particular attention was paid to the period 5 to 6 days after injection at which time the necrotizing response was at its peak and virus particles were seen in greatest numbers. The most numerous particles were about 28 mµ in diameter. They were observed mainly within nuclei of stromal cells and are similar to the particles seen in large numbers in polyoma-infected mouse cells growing in vitro. They were not observed in cells of fully developed tumors. Filamentous or tubular structures closely associated with the 28 mµ particles and probably concerned in their formation are described. Considerable quantities of viral material were contained within cytoplasmic inclusions. In some of the inclusions larger particles of diameter 60 mµ were observed. The origin of these particles and their relation to the 28 mµ particles is discussed.

DEVELOPMENT OF A METHOD FOR CONSTRUCTING AND ASSESSING THE RELIABILITY OF HYPOTHESES ABOUT THE INTERRELATION OF A COMBINATION OF CYTOKINES AND OPHTHALMIC PREPARATIONS USING AN INTELLIGENT INFORMATION SYSTEM

2021 ◽  
pp. 62-70
Author(s):  
Андрей Александрович Давыденко ◽  
Ирина Владимировна Баранникова ◽  
Виталий Вячеславович Челноков ◽  
Леонид Иванович Руссу ◽  
Марина Владимировна Мезенцева
Keyword(s):  
Information System ◽  
Inductive Inference ◽  
Cell Structure ◽  
Simultaneous Action ◽  
Ophthalmic Drugs ◽  
Subjective Factor ◽  
Intelligent Information ◽  
The Relationship ◽  
Number Of Cells

В работе рассмотрено сравнение экспериментальных распределений количества клеток для определения цитологического и иммунологического эффекта, оказываемого одновременным воздействием офтальмологических препаратов Броксинак® и Офтальмоферон® на клетки с конъюнктивы больного человека, направленное на совершенствование методики оценки комбинаций офтальмологических лекарственных средств in vitro. Доклинические исследования дают возможность определить эффективность применения лекарственных средств, возможные противопоказания и побочные эффекты, чтобы в дальнейшем определиться с объемом клинических испытаний и самой возможностью их проведения. В последнее время в различных областях медицины применяют счетчики клеток. Счетчики определяют не только количество клеток в образце, но и их размеры и объем, что позволяет сделать предположение о виде клеточной структуры. Подобные приборы позволяют автоматизировать подсчет клеток, определение их размеров и объема, что исключает субъективный фактор и возможность получения ошибочных данных, а также упрощает процедуру и позволяет получить результаты в короткий срок. На основе использования методов индуктивного вывода предложена методика построения гипотез о взаимосвязи комбинации цитокинов с пролиферативной активностью клеток. Методика учитывает синергическое взаимодействие цитокинов и использует последовательное построение логических формул для отбора групп цитокинов, статистический анализ таблиц сопряженности и логическую интеграцию полученных оценок. Реализация предложенной методики в рамках ИС позволит существенно ускорить научные исследования в этой области. Приведена итоговая методика построения гипотез о взаимосвязи комбинации цитокинов с биологической активностью клеток The paper considers a comparison of experimental distributions of the number of cells to determine the cytological and immunological effect of the simultaneous action of ophthalmic drugs Broxinac® and Oftalmoferon® on cells from the conjunctiva of a sick person, aimed at improving the methodology for assessing combinations of ophthalmic drugs in vitro. Preclinical studies make it possible to determine the effectiveness of the use of drugs, possible contraindications and side effects, in order to further determine the volume of clinical trials and the very possibility of their conduct. Recently, cell counters have been used in various fields of medicine. Counters determine not only the number of cells in the sample, but also their size and volume, which allows us to make an assumption about the type of cell structure. Such devices allow automating the counting of cells, determining their size and volume, which eliminates the subjective factor and the possibility of obtaining erroneous data, and also simplifies the procedure and allows you to get results in a short time. Based on the use of inductive inference methods, a method is proposed for constructing hypotheses about the relationship between the combination of cytokines and the proliferative activity of cells. The method takes into account the synergistic interaction of cytokines and uses the sequential construction of logical formulas for the selection of groups of cytokines, statistical analysis of contingency tables and logical integration of the estimates obtained. The implementation of the proposed methodology within the Information System will significantly accelerate research in this area. The final technique for constructing hypotheses about the relationship of the combination of cytokines with the biological activity of cells is presented

The effects of oestradiol and relaxin on extensibility and collagen organisation of the pregnant rat cervix

1995 ◽  
Vol 146 (2) ◽  
pp. 331-337 ◽  
Author(s):  
S H Cheah ◽  
K H Ng ◽  
V T Johgalingam ◽  
M Ragavan
Keyword(s):  
Electron Microscope ◽  
Light Microscope ◽  
Late Pregnancy ◽  
Collagen Fibres ◽  
Thin Sections ◽  
Pregnant Rat ◽  
And Control ◽  
Collagen Organisation

Abstract The effects of exogenously introduced oestradiol-17β (E) and relaxin (RLX) on cervical extensibility and collagen organisation were tested in rats ovariectomised in late pregnancy. When the cervices were stretched in vitro by 1 mm increments, it was found that those from rats given E alone generated significantly higher tensions than those from control rats, while cervices from rats given both E and RLX had tensions similar to controls. Examination of cervical sections under the light microscope and ultra-thin sections under the electron microscope showed that the collagen fibres in the cervices from E-treated rats were highly organised, whereas those from animals given E+RLX and control animals were disorganised and dispersed. It was concluded that E decreased cervical extensibility, while RLX counteracted the effect of E to maintain a soft and easily extensible cervix. Journal of Endocrinology (1995) 146, 331–337

Tumor promoter 12-O-tetradecanoylphorbol 13-acetate stimulates simian virus 40 induction by DNA-damaging agents and tumor initiators

1983 ◽  
Vol 3 (5) ◽  
pp. 757-760
Author(s):  
S Nomura ◽  
N Shobu ◽  
M Oishi
Keyword(s):  
Molecular Structure ◽  
Uv Irradiation ◽  
Culture Medium ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
Tumor Promoter ◽  
Kidney Cells ◽  
Sv40 Virus ◽  
Virus Particles ◽  
Dna Damaging Agents

Simian virus 40 (SV40)-transformed Syrian hamster kidney cells produce infectious SV40 virus particles after treatments which damage DNA, such as UV irradiation or mitomycin C treatment. We have found that the induction of SV40 by DNA-damaging agents is greatly stimulated when a typical tumor promoter, 12-O-tetradecanoylphorbol 13-acetate (TPA), is present in the medium. Phorbol, which has a molecular structure similar to TPA but does not have any tumor-promoting activity, showed no such stimulatory effect on SV40 induction. This apparent synergistic effect of DNA-damaging agents and tumor promoter (TPA) was more pronounced when a tumor initiator, benzo [a]pyrene or 2-acetamido-fluorene, was combined with TPA. The effect of TPA on UV-triggered SV40 induction was greatly influenced by the timing of TPA addition to the culture medium, which was most efficient when addition of TPA was 5 to 20 h before UV irradiation. The effect of TPA, however, was not observed in SV40 rescue from hamster cells by cell fusion with permissive monkey (C7) cells.

scholarly journals ELECTRON MICROSCOPE OBSERVATIONS ON INTRACELLULAR VIRUS-LIKE PARTICLES ASSOCIATED WITH THE CELLS OF THE LUCKÉ RENAL ADENOCARCINOMA

1956 ◽  
Vol 2 (6) ◽  
pp. 725-742 ◽  
Author(s):  
Don W. Fawcett
Keyword(s):  
Electron Microscope ◽  
Tumor Cells ◽  
Inclusion Bodies ◽  
Hollow Spheres ◽  
Virus Multiplication ◽  
Leopard Frog ◽  
Uniform Size ◽  
Thin Sections ◽  
Virus Particles ◽  
Renal Adenocarcinoma

The common renal adenocarcinoma of the leopard frog was studied in thin sections with the electron microscope. Approximately a third of the tumors examined were found to contain spheroidal bodies of uniform size and distinctive morphology that are believed to be virus particles. These consist of hollow spheres (90 to 100 mµ) having a thick capsule and a dense inner body (35 to 40 mµ) that is eccentrically placed within the central cavity (70 to 80 mµ). Virus particles of this kind occur principally in the cytoplasm but occasionally they are also found in the nucleus and in the extracellular spaces of the tumor. The intranuclear inclusion bodies that are visible with the light microscope are largely comprised of hollow, spherical vesicles with thin limiting membranes. These are embedded in a finely granular matrix. A few of the thin walled vesicles contain a dense inner body like that of the cytoplasmic virus particles. This suggests that they may be immature virus particles. The inclusion bodies are believed to be formed in the course of virus multiplication but they usually contain very few mature virus particles. Bundles of dense filaments and peculiar vacuolar inclusions also occur in the cytoplasm of the tumor cells. These seem to be related in some way to the presence of virus but their origin and significance remain obscure. These findings are discussed in relation to previous work suggesting that the Lucké adenocarcinoma is caused by an organ-specific filtrable agent. It is concluded that the "virus particles" found in electron micrographs of the tumor cells may be the postulated tumor agent. On the other hand, the possibility remains that the particles described here are not those that are causally related to the tumors.

scholarly journals THE PARTICIPATION OF NUCLEOTIDE IN THE FORMATION OF PHOSPHATASE REACTION PRODUCT: A CHEMICAL AND ELECTRON MICROSCOPE AUTORADIOGRAPHIC STUDY

1969 ◽  
Vol 17 (12) ◽  
pp. 839-847 ◽  
Author(s):  
ALAN S. ROSENTHAL ◽  
HAROLD L. MOSES ◽  
CHARLES E. GANOTE ◽  
LOIS TICE
Keyword(s):  
Electron Microscope ◽  
Adenosine Triphosphatase ◽  
Autoradiographic Study ◽  
In Vitro Studies ◽  
Lead Salt ◽  
Cellular Distribution ◽  
Lead Phosphate ◽  
Relationship Of ◽  
The Relationship

Data are presented which show that the reaction product formed in adenosine triphosphatase cytochemical procedures is not simple lead phosphate. Both by chemical and electron microscope autoradiographic techniques, reaction product was found to contain nucleotide as well as lead and phosphate. Nearly equimolar quantities of nucleotide and phosphate are present in tissue incubated in a standard Wachstein-Meisel medium. Electron microscope autoradiographs demonstrate that nucleotide is uniformly associated with adenosine triphosphatase reaction product, regardless of its cellular distribution. In vitro studies of the interaction of nucleotide with lead and phosphate are also presented. The relationship of these observations to the validity of lead-salt cytochemical procedures is discussed.

scholarly journals Regulatory properties of vitronectin and its glycosylation in collagen fibril formation and collagen-degrading enzyme cathepsin K activity

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kimie Date ◽  
Hiromi Sakagami ◽  
Kei Yura
Keyword(s):  
Extracellular Matrix ◽  
Collagen Fibril ◽  
Molecular Mechanisms ◽  
Close Contact ◽  
Cathepsin K ◽  
Fibril Formation ◽  
Collagen Fibers ◽  
Acid Solubility ◽  
The Relationship

AbstractVitronectin (VN) is a glycoprotein found in extracellular matrix and blood. Collagen, a major extracellular matrix component in mammals, is degraded by cathepsin K (CatK), which is essential for bone resorption under acidic conditions. The relationship between VN and cathepsins has been unclear. We discovered that VN promoted collagen fibril formation and inhibited CatK activity, and observed its activation in vitro. VN accelerated collagen fibril formation at neutral pH. Collagen fibers formed with VN were in close contact with each other and appeared as scattered flat masses in scanning electron microscopy images. VN formed collagen fibers with high acid solubility and significantly inhibited CatK; the IC50 was 8.1–16.6 nM and competitive, almost the same as those of human and porcine VNs. VN inhibited the autoprocessing of inactive pro-CatK from active CatK. DeN-glycosylation of VN attenuated the inhibitory effects of CatK and its autoprocessing by VN, but had little effect on acid solubilization of collagen and VN degradation via CatK. CatK inhibition is an attractive treatment approach for osteoporosis and osteoarthritis. These findings suggest that glycosylated VN is a potential biological candidate for CatK inhibition and may help to understand the molecular mechanisms of tissue re-modeling.

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