Reversible inhibition of chondrogenic expression by certain hyaluronidase preparations

Embryonic chick chondrocytes were cultured in the presence or absence of different preparations of testicular hyaluronidase. This treatment inhibited the accumulation of cartilage matrix as indicated by phase-contrast microscopy, by Alcian green staining, and by accumulation of 35S-labeled material. In addition, most preparations of testicular hyaluronidase caused a conversion of the cells to a fibroblastic phenotype characterized by a faster growth rate and the synthesis of type-1 collagen. This effect was found to beconcentrationdependent and was not observed at the minimum concentration of hyaluronidase required toinhibit matrix accumulation. Since two more highly purified hyaluronidase preparations prevented matrix accumulation but did not cause the fibroblastic transformation, it is likely that the conversion to a fibroblastic phenotype is caused by a contaminant in the other hyaluronidase preparations.

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Compound sensilla in monogenean skin parasites

Parasitology ◽

10.1017/s0031182000031164 ◽

1969 ◽

Vol 59 (3) ◽

pp. 625-636 ◽

Cited By ~ 43

Author(s):

Kathleen M. Lyons

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Phase Contrast ◽

The Other ◽

Phase Contrast Microscopy ◽

Sense Organs ◽

Dense Membrane ◽

Contrast Microscopy ◽

Membrane Bound

The fine structure of two kinds of compound presumed sense organs from the heads of three skin parasitic monogeneans Gyrodactylus sp. Entobdella soleae (larva only) and Acanthocotyle elegans is described. One kind of compound receptor consists of a number of associated sensilla, each ending in a single cilium (the spike sensilla of Gyrodactylus and the cone sensilla of E. soleae oncomiracidium).The other kind of compound organ is made up of one or a few neurones only, each of which bears many cilia (pit organs of E. soleae oncomiracidium and feeding organ sensilla of Acanthocotyle elegans). The spike sensilla of Gyrodactylus have also been studied using a Cambridge Instrument Co. Stereoscan electron microscope and by phase-contrast microscopy. The ciliary endings of all these sense organs are highly modified and have lost the 9 + 2 structure, being packed with many fibres. The fibre arrangement in the cilia of the cone sensillae of E. soleae oncomiracidium and the feeding organ sensilla of A. elegans has been compared with that in the ciliary endings of other invertebrate mechano- and chemoreceptors. The possibility that the spike sensilla of Gyrodactylus may be chemoreceptors has been discussed but it is considered premature to attempt to assign functions to the other sense organs studied. Electron dense membrane-bound inclusions occurring specifically in the nerves supplying the spike sensilla of Gyrodactylus may be neurosecretory.

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Action of Factor XIII on Transamidation Bounds between the Collagen Molecule Constituents

10.1055/s-0039-1689317 ◽

1975 ◽

Author(s):

J. Soria ◽

G. Soria ◽

G. Boulard

Keyword(s):

Molecular Weight ◽

Gel Electrophoresis ◽

Factor Xiii ◽

Phase Contrast ◽

Polyacrylamide Gel Electrophoresis ◽

The Other ◽

Polymerization Process ◽

Collagen Molecule ◽

Phase Contrast Microscopy ◽

Contrast Microscopy

By polyacrylamide gel electrophoresis in the presence of SDS we observed that collagen polymerized in the presence of factor XIII a, is dissociated by urea into sub-units with a higher molecular weight than that polymerized in the absence of factor XIII.In the other hand, by phase contrast microscopy we have found that the structure of collagen is quite different when the polymerization process takes place in the presence or in the absence of activated factor XIII.This modification of collagen polymerization in the presence of factor XIII a possibly acts in wound healing.

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Counting dead spermatozoa in frozen semen

Animal Science ◽

10.1017/s0003356100022285 ◽

1965 ◽

Vol 7 (1) ◽

pp. 59-65 ◽

Cited By ~ 5

Author(s):

H. R. L. Buttle ◽

J. L. Hancock ◽

A. F. Purser

Keyword(s):

Analysis Of Variance ◽

Sodium Fluoride ◽

Phase Contrast ◽

Egg Yolk ◽

The Other ◽

Phase Method ◽

Phase Contrast Microscopy ◽

Frozen Semen ◽

Contrast Microscopy ◽

Differential Counts

SUMMARYThree methods were used to make differential counts of living and dead bull spermatozoa in samples of frozen semen in an egg-yolk citrate medium containing glycerol.With two methods (‘phase’ and ‘nigrosin’ methods) dead spermatozoa were identified by their altered structure. With a third method (nigrosineosin) dead spermatozoa were identified by their staining affinity. With the phase method spermatozoa were immobilised by treatment with approximately M/40 sodium fluoride and were examined by phase-contrast microscopy in unfixed wet preparations. With the other two methods the spermatozoa were examined in smears stained either with nigrosin alone (nigrosin method) or with nigrosin and eosin (nigrosin-eosin method).Analysis of variance of the results of a factorial experiment involving fluoride-treated and untreated samples from 6 bulls with the three methods showed that differences between semen samples contributed 66% of the variation. A defect of the phase method was that the variance between counts was greater than the theoretically expected value.All spermatozoa in nigrosin-eosin stained preparations were stained with eosin within a few days of the smears being made, so that living and dead spermatozoa could not be distinguished by their differing affinities for eosin. Repeat counts on nigrosin-stained preparations did not differ significantly from counts made several days previously. Sodium fluoride in the concentration used here (M/40) tended to reduce the percentage of dead spermatozoa.

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Application of Phase Contrast Microscopy in Gemmology

The Journal of Gemmology ◽

10.15506/jog.1957.6.4.151 ◽

1957 ◽

Vol 6 (4) ◽

pp. 151-165 ◽

Cited By ~ 1

Author(s):

E. J. Gübelin

Keyword(s):

Phase Contrast ◽

Phase Contrast Microscopy ◽

Contrast Microscopy

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Direct Observation of Femtosecond Laser Induced Modifications in the Bulk of Fused Silica by Phase Contrast Microscopy

Journal of Laser Micro/Nanoengineering ◽

10.2961/jlmn.2006.03.0001 ◽

2006 ◽

Vol 1 (3) ◽

pp. 155-160 ◽

Cited By ~ 7

Author(s):

Alexandre Mermillod-Blondin

Keyword(s):

Femtosecond Laser ◽

Direct Observation ◽

Phase Contrast ◽

Fused Silica ◽

Phase Contrast Microscopy ◽

Contrast Microscopy

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Rough Dental Implant Surfaces and Peri-Implantitis: Role of Phase-Contrast Microscopy, Laser Protocols, and Modified Home Oral Hygiene in Maintenance. A 10-Year Retrospective Study

Applied Sciences ◽

10.3390/app11114985 ◽

2021 ◽

Vol 11 (11) ◽

pp. 4985

Author(s):

Gianluigi Caccianiga ◽

Gérard Rey ◽

Paolo Caccianiga ◽

Alessandro Leonida ◽

Marco Baldoni ◽

...

Keyword(s):

Retrospective Study ◽

Phase Contrast ◽

Vertical Movement ◽

Subgingival Plaque ◽

Phase Contrast Microscopy ◽

Implant Surface ◽

Total Percentage ◽

Contrast Microscopy

The aim of this study was to evaluate two different kinds of rough implant surface and to assess their tendency to peri-implantitis disease, with a follow-up of more than 10 years. Data were obtained from a cluster of 500 implants with Ti-Unite surface and 1000 implants with Ossean surface, with a minimum follow-up of 10 years. Implants had been inserted both in pristine bone and regenerated bone. We registered incidence of peri-implantitis and other causes of implant loss. All patients agreed with the following maintenance protocol: sonic brush with vertical movement (Broxo), interdental brushes, and oral irrigators (Broxo) at least two times every day. For all patients with implants, we evaluated subgingival plaque samples by phase-contrast microscopy every 4 months for a period of more than 10-years. Ti-Unite surface implants underwent peri-implantitis in 1.6% of the total number of implants inserted and Ossean surface implants showed peri-implantitis in 1.5% of the total number of implants. The total percentage of implant lost was 4% for Ti-Unite surfaces and 3.6% for Ossean surfaces. Strict control of implants leads to low percentage of peri-implantitis even for rough surfaces dental implants.

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