California encephalitis virus proliferation in Yukon mosquitoes incubated at low temperatures

1976 ◽  
Vol 22 (8) ◽  
pp. 1128-1136 ◽  
Author(s):  
D. M. McLean ◽  
P. N. Grass ◽  
B. D. Judd ◽  
K. S. K. Wong
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Salivary Glands ◽  
Low Temperatures ◽  
Acinar Cells ◽  
Yukon Territory ◽  
Immunoperoxidase Staining ◽  
Snowshoe Hare ◽  
Intrathoracic Inoculation ◽  
Aedes Communis

Replication of a subarctic Bunyavirus, California encephalitis (snowshoe hare subtype), was detected in salivary glands and thoraces of wild-caught Aedes communis mosquitoes from the Yukon Territory, after intrathoracic inoculation with 0.1 to 100 mouse LD50 virus, and incubation for 7 to 21 days throughout their viable temperature range of 0 to 23 °C. Immunoperoxidase staining confirmed that viral replication occurred in the cytoplasm of acinar cells of salivary glands, both by light microscopy and electron microscopy. Replication of another subarctic Bunyavirus. Northway, and a subtropical Flavivirus, Murray Valley encephalitis, was also demonstrated by infectivity titrations and immunoperoxidase reactions in salivary glands of A. communis incubated at 0, 13, and 23 °C for 7 to 21 days.

California encephalitis virus development in mosquitoes as revealed by transmission studies, immunoperoxidase staining, and electron microscopy

1975 ◽  
Vol 21 (4) ◽  
pp. 453-462 ◽  
Author(s):  
D. M. McLean ◽  
S. M. Gubash ◽  
P. N. Grass ◽  
M. A. Miller ◽  
M. Petric ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Salivary Glands ◽  
Immunoperoxidase Staining ◽  
Snowshoe Hare ◽  
Immunoperoxidase Technique ◽  
Thin Sections ◽  
Before And After ◽  
Culiseta Inornata ◽  
Transmission Studies ◽  
Marsh Lake

Isolates of the snowshoe hare subtype of California encephalitis (CE) virus from Yukon mosquitoes during 1972 and 1973 were transmitted by bites of Aedes aegypti mosquitoes after 4 to 5 weeks of extrinsic incubation at 55°F after intrathoracic injection, and the 1973 strain was transmitted after mosquitoes were fed virus and held for 3 to 4 weeks at 75°F. Antigen of a 1971 isolate of CE virus (Marsh Lake 23) was detected in salivary glands of infected mosquitoes by the immunoperoxidase technique, using highly purified antiserum before and after conjugation with horseradish peroxidase, plus the use of orthotolidine as a substitute for benzidine. Enveloped virions 45 nm in diameter were observed in thin sections of salivary glands of Culiseta inornata mosquitoes 59 days after intrathoracic injection with the 1971 isolate, after incubation at 55°F.

scholarly journals Morphologic Characteristics of the Submandibular Salivary Gland of the Collared Peccary (Tayassu Tajacu)

2018 ◽  
Vol 35 (02) ◽  
pp. 116-121
Author(s):  
Gabriela de Souza Reginato ◽  
Cristina de Sousa Bolina ◽  
Moacir Franco Oliveira ◽  
Sonia Regina Yokomizo Almeida ◽  
Ii-sei Watanabe ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Salivary Gland ◽  
Salivary Glands ◽  
Secretory Granules ◽  
Morphological Characteristics ◽  
Acinar Cells ◽  
Collagen Fibers ◽  
Submandibular Salivary Gland ◽  
Ductal Cells ◽  
Collared Peccary

Introduction Most salivary glands is located on the inside and around the oral cavity, and are divided into major and minor salivary glands. The aim of the present study was to describe the structural and ultrastructural morphological characteristics of the lingual tissue of the submandibular glands of the collared peccary (Tayassu tajacu). Materials and Methods The submandibular glands (n = 10) of adult male collared peccaries ( T. tajacu) were used for histological and ultrastructural analysis. The techniques used were light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results The submandibular salivary glands of the collared peccary (T. tajacu) showed a capsule formed by a connective tissue containing the acinus and duct cells. Histologically, the nuclei located at the basal region of the cells was observed. The light polarized microscopy clearly showed the presence of type I and type III collagen. In the SEM image, the submandibular salivary gland revealed a round aspect separated in several lobules with bundles of collagen fibers. The vibratome sections showed the groupings of acinar cells, with intermingled secretory ducts containing vessels of different diameters. The secretory granules were noted in the apical portion of the acinar and ductal cells. The thick bundles of collagen fibers formed a glandular capsule and were identified around of the acinar and ductal cells in three-dimensional SEM images. The TEM images showed a number of secretory granules, especially in the apical region of the cytoplasm of the acinar cells and in the basal portion of the nuclei. The granular endoplasmic reticulum area, the euchromatic nuclei and the cytoplasmic projections may be seen. Mucous acinar cells separated by fine collagen fibers were also observed. Conclusion The morphological characteristics of the submandibular gland of the collared peccary is similar to that of other mammals with the same eating habits and habitat.

scholarly journals Bunyavirus isolations from mosquitoes in the western Canadian Arctic

1977 ◽  
Vol 79 (1) ◽  
pp. 61-71 ◽  
Author(s):  
D. M. McLean ◽  
P. N. Grass ◽  
B. D. Judd ◽  
L. V. Ligate ◽  
K. K. Peter
Keyword(s):  
Salivary Glands ◽  
Northwest Territories ◽  
Viral Antigen ◽  
Canadian Arctic ◽  
Encephalitis Virus ◽  
Snowshoe Hare ◽  
Infection Rates ◽  
Natural Vector ◽  
Culiseta Inornata ◽  
Aedes Communis

SUMMARYStrains of California encephalitis virus (snowshoe hare subtype) were isolated from 8 of 475 pools comprising 23747 unengorged female mosquitoes of five species collected at three of six locations throughout the Mackenzie Valley of the Northwest Territories, Canada, from latitudes 60 to 69° N between 10 and 24 July 1976. Minimum field infection rates included 1:2734 for Aedes communis, 1:256 to 1:3662 for A. hexodontus and 1:911 to 1:1611 for A. punctor. Northway virus was also isolated from 1 of 3662 A. hexodontus mosquitoes collected at Inuvik (69° N, 135° W). Transmission of CE virus by A. communis infected by feeding on virus in defibrinated blood and incubation at 0, 13 and 23 °C for 13–20 days clearly demonstrates the importance of this species as a natural vector, and transmission of CE virus by Culiseta inornata after incubation at 0 and 13 °C following intrathoracic injection strengthens evidence of its role as a natural vector. Immunofiuorescence was less reliable than imunoperoxidase for detection of CE viral antigen in mosquito salivary glands.

scholarly journals California encephalitis virus endemicity in the Yukon Territory, 1972

1973 ◽  
Vol 71 (2) ◽  
pp. 391-402 ◽  
Author(s):  
D. M. McLean ◽  
Alison M. Clarke ◽  
E. J. Goddard ◽  
A. S. Manes ◽  
C. A. Montalbetti ◽  
...  
Keyword(s):  
Yukon Territory ◽  
Ground Squirrels ◽  
Lepus Americanus ◽  
Encephalitis Virus ◽  
Tamiasciurus Hudsonicus ◽  
Snowshoe Hare ◽  
Snowshoe Hares ◽  
Tree Squirrels ◽  
Culiseta Inornata ◽  
Aedes Communis

SUMMARYSera from 218 of 1574 (14%) small mammals collected in the Yukon Territory between 14 May and 13 August 1972 neutralized a Yukon strain of California encephalitis virus (snowshoe-hare subtype). These included 133 of 319 (42%) snowshoe hares (Lepus americanus), 84 of 1243 (7%) ground squirrels (Citellus undulatus) and 1 of 12 (8%) tree squirrels (Tamiasciurus hudsonicus). California encephalitis virus (snow-shoe hare subtype) was isolated from four pools of unengorged Aedes communis mosquitoes collected near Whitehorse (61° N., 135° W.) and on one occasion each from pools of the same species collected at Hunker Creek (64° N., 138° W.) and at mile 125, Dempster Highway (66° N., 138° W.) during July 1972. Replication of a Yukon strain of California encephalitis virus was observed in wild-caught Culiseta inornata and Aedes canadensis mosquitoes after intrathoracic injection and holding at temperatures of 80°, 50° and 40° F.

Canadian bunyavirus morphogenesis in arctic mosquitoes

1978 ◽  
Vol 36 (2) ◽  
pp. 380-381
Author(s):  
K. K. Wong ◽  
D. M. McLean
Keyword(s):  
Electron Microscope ◽  
Salivary Glands ◽  
Canadian Arctic ◽  
Osmic Acid ◽  
Snowshoe Hare ◽  
Thin Sections ◽  
Aedes Communis

Morphogenesis of two Canadian Bunyavirus isolates, the snowshoe háre subtype of California encephalitis (CE) virus, and Northway (NOR) virus, has been studied in salivary glands of wild-caught Aedes communis mosquitoes from the Western Canadian Arctic. An Australian flavivirus, Murray Valley encephalitis (MVE) virus has also been studied in these mosquitoes. Female mosquitoes were inoculated intrathoracically with 100-1000 mouse LD50 CE or MVE virus or 300 plaque forming units NOR virus. Mosquitoes were incubated at 13°C for extended periods, after which salivary glands were dissected away from mosquitoe thoraces. With the proboscis attached, glands were fixed with glutaraldehyde and postfixed with osmic acid before embedding in Epon 812. Thin sections of salivary glands were examined, using a Philips EM-300 electron microscope. Infectivity titrations of salivary glands or thoraces of the same batch of mosquitoes were performed whenever possible.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

Tumor Diagnosis

1982 ◽  
Vol 40 ◽  
pp. 262-265
Author(s):  
Bruce Mackay
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Differential Diagnosis ◽  
Light Microscopy ◽  
Clinical Examination ◽  
Ultrastructural Study ◽  
Diagnostic Procedures ◽  
Specific Diagnosis ◽  
Transmission Electron ◽  
Microscopic Diagnosis

The broadest application of transmission electron microscopy (EM) in diagnostic medicine is the identification of tumors that cannot be classified by routine light microscopy. EM is useful in the evaluation of approximately 10% of human neoplasms, but the extent of its contribution varies considerably. It may provide a specific diagnosis that can not be reached by other means, but in contrast, the information obtained from ultrastructural study of some 10% of tumors does not significantly add to that available from light microscopy. Most cases fall somewhere between these two extremes: EM may correct a light microscopic diagnosis, or serve to narrow a differential diagnosis by excluding some of the possibilities considered by light microscopy. It is particularly important to correlate the EM findings with data from light microscopy, clinical examination, and other diagnostic procedures.

Immunocytochemistry. A Review of Methodology for Electron Microscopic Applicaiton

1974 ◽  
Vol 32 ◽  
pp. 328-329
Author(s):  
Joseph E. Mazurkiewicz
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Ultrastructural Level ◽  
Electron Microscopic ◽  
Biological Interest ◽  
Investigative Approach ◽  
Immunologic Activity ◽  
Dense Label

Immunocytochemistry is a powerful investigative approach in which one of the most exacting examples of specificity, that of the reaction of an antibody with its antigen, isused to localize tissue and cell specific molecules in situ. Following the introduction of fluorescent labeled antibodies in T950, a large number of molecules of biological interest had been studied with light microscopy, especially antigens involved in the pathogenesis of some diseases. However, with advances in electron microscopy, newer methods were needed which could reveal these reactions at the ultrastructural level. An electron dense label that could be coupled to an antibody without the loss of immunologic activity was desired.

Electron Microscopy of Mycoplasma Pneumoniae

1971 ◽  
Vol 29 ◽  
pp. 258-259 ◽  
Author(s):  
E. S. Boatman ◽  
G. E. Kenny
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Growth Phase ◽  
Hela Cells ◽  
Sulfonic Acid ◽  
Gamma Globulin ◽  
Horse Serum ◽  
Morphological Aspects ◽  
The Family

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.

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