Banded filaments associated with the aster yellows MLO in Vinca rosea L.

1978 ◽  
Vol 24 (11) ◽  
pp. 1417-1418 ◽  
Author(s):  
D. E. Carling ◽  
D. F. Millikan
Keyword(s):  
Aster Yellows ◽  
Characteristic Morphology ◽  
Vinca Rosea ◽  
Electron Lucent

The ultrastructure of an aster yellows mycoplasma-like organism was studied in the phloem of periwinkle (Vinca rosea L.) plants. Banded filaments were observed in association with mycoplasma-like organisms of characteristic morphology. The filaments were variable in length, from 50–100 nm in width, and displayed a regular periodic banding of alternating electron-dense and electron-lucent structures.

A YELLOWS-TYPE VIRUS OF ALSIKE CLOVER IN ALBERTA

1965 ◽  
Vol 43 (5) ◽  
pp. 527-536 ◽  
Author(s):  
L. N. Chiykowski
Keyword(s):  
Daucus Carota ◽  
Type Virus ◽  
Nicotiana Rustica ◽  
Aster Yellows ◽  
Daucus Carota L ◽  
Vinca Rosea ◽  
Clover Phyllody

A yellows-type virus was isolated from naturally infected alsike clover, Trifolium hybridum L., from Alberta by means of the six-spotted leafhopper, Macrosteles fascifrons (Stål), and transmitted to T. hybridum, Callistephus chinensis Nees, Vinca rosea L., Daucus carota L., and Nicotiana rustica L. Attempts to isolate the virus with Scaphytopius acutus (Say) were unsuccessful. On the basis of symptomatology and vector–virus relationships it is concluded that this virus is distinct from the clover phyllody virus and known strains of the aster yellows virus. The name, clover proliferation virus, is proposed. Symptoms produced on hosts are illustrated and discussed.

The preservation of membranes of tubular bodies associated with mycoplasmalike organisms by tannic acid

1978 ◽  
Vol 56 (22) ◽  
pp. 2878-2882 ◽  
Author(s):  
M. H. Chen ◽  
C. Hiruki
Keyword(s):  
Tannic Acid ◽  
Membrane Structure ◽  
Unit Membrane ◽  
Aster Yellows ◽  
Vinca Rosea ◽  
Common Unit ◽  
Hollow Cylinders ◽  
Tubular Body ◽  
Tubular Bodies ◽  
Mycoplasmalike Organisms

Fixation with a mixture of tannic acid and paraformaldehyde–glutaraldehyde resulted in an increased electron density of the membrane structure of tubular bodies that were associated with mycoplasma organisms (MLO) in Vinca rosea plants infected with the Alberta isolate of the aster yellows agent. The tubular bodies, 25.5 ± 4.3 nm in diameter, were bounded with membranes in contrast with the hollow cylinders of 12.3 ± 3.0 nm in conventional fixation. In the study of physical relationships, the tubular bodies were often connected with MLO by a common unit membrane. Some subtubules were formed from a main tubular body.

SCAPHYTOPIUS ACUTUS (SAY), A NEWLY DISCOVERED VECTOR OF CELERY-INFECTING ASTER-YELLOWS VIRUS

1962 ◽  
Vol 40 (6) ◽  
pp. 799-801 ◽  
Author(s):  
L. N. Chiykowski
Keyword(s):  
Incubation Period ◽  
Incubation Time ◽  
Trifolium Repens ◽  
Feeding Period ◽  
Aster Yellows ◽  
Vinca Rosea ◽  
Trifolium Repens L ◽  
Test Plants

Scaphytopius acutus (Say) transmitted a celery-infecting strain of aster-yellows virus from infected periwinkle (Vinca rosea L.) and aster (Callistephus chinensis Nees) to periwinkle, aster, and ladino clover (Trifolium repens L.). It acquired the virus during feeds as short as 4 hours, and transmitted it during a 2-hour feeding period. The minimum incubation time for the virus in the insect was between 21 and 26 days. After an acquisition feed of 7 days and an incubation period of at least 30 days, 11 of 21 insects transmitted the virus to separate periwinkle test plants.

CLOVER PHYLLODY VIRUS IN CANADA AND ITS TRANSMISSION

1962 ◽  
Vol 40 (3) ◽  
pp. 397-404 ◽  
Author(s):  
L. N. Chiykowski
Keyword(s):  
Nova Scotia ◽  
New Brunswick ◽  
Trifolium Repens ◽  
Prince Edward Island ◽  
Trifolium Pratense ◽  
Aster Yellows ◽  
Vinca Rosea ◽  
Trifolium Pratense L ◽  
Trifolium Repens L ◽  
Clover Phyllody

Phyllody in clovers, observed on rare occasions in Canada since 1902, is now common in Quebec, New Brunswick, Nova Scotia, and Prince Edward Island. Tests in the field indicated that natural spread of the disease could occur each month from June to September. A virus causing phyllody symptoms was transmitted by the leafhoppers Macrosteles fascifrons (Stal), Aphrodes bicinctus (Schrank), and Scaphytopius acutus (Say) from Trifolium repens L. to T. repens. M. fascifrons also transmitted the virus to and from Vinca rosea L. and Callistephus chinensis Nees. S. acutus transmitted the virus to V. rosea and Trifolium pratense L. The virus was also transmitted by dodder, Cuscuta gronovii Willd., from V. rosea to V. rosea. Clover phyllody virus (CPV) in Canada resembles CPV in England and Europe and both are transmitted by A. bicinctus. Although CPV in Canada is transmitted by M. fascifrons, which is a vector of aster-yellows virus (AYV), it differs from recognized strains of AYV in other vector–virus relationships, symptomatology, and geographic distribution.

Uultrastructure of Microtubules

1972 ◽  
Vol 30 ◽  
pp. 252-253
Author(s):  
Ariaki Nagayama
Keyword(s):  
Fine Structure ◽  
Cultured Cells ◽  
Present Report ◽  
Confluent Monolayer ◽  
Purification Method ◽  
Vinca Rosea ◽  
L Cells ◽  
Antimitotic Activity ◽  
Monolayer Cultures ◽  
Rapid Purification

Vinblastine(Vb) or vincristine, alkaloid derived from Vinca rosea is known for its antimitotic activity by regrouping of microtubules into paracrystalline form within the cells. A rapid purification method of vinblastine-induced microtubular paracrystals(PC) has provided us with a fresh and pure microtubular material demonstrating the presence of a labile ATPase associated with the PC. The present report is concerned with the fine structure of purified microtubules of mammalian cultured cells.Confluent monolayer cultures of L cells were incubated for 20hrs with 10-5 M Vb (donated from Shionogi Seiyaku & Co., Osaka, Japan).

Vesicular system associated with spermiogenesis of bullfrog

1987 ◽  
Vol 45 ◽  
pp. 818-819
Author(s):  
K. C. Liu ◽  
S. F. Tsay
Keyword(s):  
Electron Microscopy ◽  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Reproductive System ◽  
Seminiferous Tubule ◽  
Rana Catesbeiana ◽  
Routine Procedure ◽  
Electron Microscopic ◽  
Twisted Tubules ◽  
Electron Lucent

In the histologic and electron microscopic study of the male reproductive system of bullfrog, Rana catesbeiana, a vesicular system associated with spermiogenesis was observed. It appeared in the lumenal space of the seminiferous tubule (Fig. 1), in the heads of spermatids (Fig. 2), associated with the chromatins of the spermatid (Fig. 4). As deduced from sections, this vesicular system consisted of vesicles of various size or a large group of waving and twisted tubules (Fig. 3), After routine procedure of treatment for electron microscopy, the lumens of both of the vesicles and tubules were electron lucent.In human, vesicles and vesicular system associated with reproductive cell and tissue were reported. In abnormal spermiogenesis, flower-like body, actually vesicles, and giant vesicle associated with the head of spermatid were observed. In both cases the number of vesicle was limited from a single one to a few.

Effect of brefeldin A (BFA) on the unique surface coat of pulmonary intravascular macrophages (PIMs) of sheep: Ultrastructural and cytochemical study

1993 ◽  
Vol 51 ◽  
pp. 18-19
Author(s):  
Baljit Singh
Keyword(s):  
Brefeldin A ◽  
Ultrastructural Feature ◽  
Surface Coat ◽  
Anterograde Transport ◽  
Cytochemical Study ◽  
Active Involvement ◽  
Electron Lucent ◽  
Pulmonary Intravascular Macrophages ◽  
Unique Surface

The PIM of sheep, calf, goat and horse has a characteristic ultrastructural feature in the form of a unique, heparin sensitive, globular surface coat present around the plasma membrane with an intervening electron lucent space of 32-40 nm. We previously showed the active involvement of this surface coat in the phagocytosis of tracer material like monastral blue and cationized ferritin. The surface coat is capable of reconstitution in vivo following disruption with heparin. The present study was aimed to investigate whether PIM is the source of surface coat or not. In the recent years the BFA has been extensively used to understand the secretory pathways in the cells because of its ability to cause a rapid and reversible block to the anterograde transport of proteins from the endoplasmic reticulum to the Golgi.Sheep (n=6) were weighed, their plasma volume was calculated indirectly and based on which a sufficient single intravenous dose of BFA was given so as to reach a concentration of 4-5 microgram/ml of plasma.

Evaluation of platelet dense granules for determining storage pool deficiencies by HVEM image and quantitative analysis

1996 ◽  
Vol 54 ◽  
pp. 770-771
Author(s):  
W.T. Gunning ◽  
J.N. Turner ◽  
K. Buttle ◽  
E.P. Calomeni ◽  
N.A. Lachant ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Platelet Function ◽  
Electron Microscopic ◽  
Von Willebrand's Disease ◽  
Dense Granules ◽  
Storage Pool ◽  
Prolonged Bleeding ◽  
Microscopic Evaluation ◽  
Storage Pools ◽  
Electron Lucent

There are a variety of conditions which have been associated with prolonged bleeding times. If other etiologies including von Willebrand's disease have been ruled out, a platelet function disorder must be considered. The best, if not only, technique to make this diagnosis is the electron microscopic evaluation of whole air dried platelets. Bull first described the presence of dense granules in whole platelets in 1968 and the technique has been utilized extensively The electron dense or delta granules are easily distinguished from the larger more numerous alpha granules which are electron lucent. The significance of the dense granules is that they are known to be “storage pools” of serotonin, calcium, adenosine di- and triphosphate, and pyrophosphate. Prolonged bleeding times may be directly related to an insufficiency of these substances. The diagnosis of a storage pool deficiency is made when either the storage content of the dense granules is abnormal or their number is diminished. We observe normal platelets to have 4-6 dense granules, which agrees with the literature.

The Ullrastructure of Platelet Participation in Hemostasis

1965 ◽  
Vol 13 (01) ◽  
pp. 065-083 ◽  
Author(s):  
Shirley A. Johnson ◽  
Ronaldo S. Balboa ◽  
Harlan J. Pederson ◽  
Monica Buckley
Keyword(s):  
Platelet Aggregation ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Guinea Pigs ◽  
Platelet Factor ◽  
Mesenteric Vessels ◽  
Platelet Aggregates ◽  
Electron Lucent

SummaryThe ultrastructure of platelet aggregation in vivo in response to bleeding brought about by transection of small mesenteric vessels in rats and guinea pigs has been studied. Platelets aggregate, degranulate and separating membranes disappear in parallel with fibrin appearance which is first seen at several loci after 30 seconds of bleeding. About 40 per cent of the electron opaque granules, some of which contain platelet factor 3 have disappeared after one minute of bleeding while the electron lucent granules increase by 70 per cent suggesting that some of them may be empty vesicles. Most of the platelet aggregates of the random type disappear leaving clumped red blood cells entrapped by a network of fibrin fibers which emanate from the remains of platelet aggregates of the rosette type to maintain hemostasis.

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