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1.
Small,Round-Structured Viruses (SRSVs) Associated with Acute Gastroenteritis Outbreaks in Gifu,Japan
Hiroyoshi Kawamoto Sumiyo Hasegawa Seiko Sawatari Chieko Miwa Osayuki Morita Takehiko Hosokawa Hiroshi Tanaka 《Microbiology and immunology》1993,37(12):991-997
Two outbreaks of non-bacterial gastroenteritis occurred in Gifu prefecture in January 1989 and in January 1991. Both outbreaks were closely related to the consumption of raw oysters, and showed similar clinical features. Small, round-structured virus particles were found in patient stools in both outbreaks by electron microscopy. The role of these particles as the causative agents of the outbreaks were strongly suggested by immune electron microscopy and/or western-blotting immunoassay. When compared with SRSV-9 (Tokyo/SRSV/86–510) reported previously (Hayashi et al, J. Clin. Microbiol., 27: 1728–1733, 1989), it was found that these viral particles were antigenically similar to SRSV-9, and had a major structural protein of 63 kilodaltons (kDa). Further, the prevalence of this agent in Gifu area was examined by western blot antibody assay using 67 serum samples collected from the inhabitants in 1991. The results indicated the circulation of the same or antigenically similar agent in this area. 相似文献
2.
Pattern of shedding of small, round-structured virus particles in stools of patients of outbreaks of food-poisoning from raw oysters 总被引:4,自引:0,他引:4
The pattern of shedding of the small, round-structured virus (SRSV) particles in the stools of patients who suffered from food-poisoning due to raw oysters was investigated. The duration and concentration of fecal shedding of the SRSV particles were studied by electron microscopic examinations of stool specimens obtained during the course of illness to see a relation of viral shedding to day of illness. It was found that the fecal shedding of the SRSV particles occurred within five days of illness; thereafter, the concentration of the SRSV particles in feces rapidly decreased within a few days during the course of illness. 相似文献
3.
Small round structured virus associated with an outbreak of acute gastroenteritis in Chiba, Japan 总被引:1,自引:0,他引:1
K Kasuga M Tokieda M Ohtawara E Utagawa S Yamazaki 《Japanese journal of medical science & biology》1990,43(4):111-121
In an outbreak of acute gastroenteritis which originated in a restaurant in Chiba, Japan, in December, 1987, small round structured virus (SRSV) particles were observed by electron microscopy in 14 of 16 stool specimens from patients. The particles were 30 to 35 nm in diameter, possessed amorphous surface structure surrounded by fine projections and had a buoyant density of 1.36 to 1.37 g/ml in cesium chloride. Serological responses to the SRSV were found by immune electron microscopy and Western blot (WB) assay in paired sera of 12 of 19 patients. Furthermore, WB analysis revealed that the antibody against SRSV was cross-reactive to other SRSV, Tokyo 86/510. 相似文献
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Small, round-structured viruses (SRSV) were detected in 14 of 300 fecal specimens obtained from patients with acute gastroenteritis by electron microscopy. These SRSV strains were morphologically indistinguishable from one another. While 11 of these strains had a single usual major structural protein with molecular weight of 63,000 (63K) daltons (p63), interestingly, three strains possessed a single major structural protein with molecular weight of 33K daltons (p33). Treatments of p63-SRSV with proteolytic enzymes or denaturating reagents did not affect the molecular weight of p63, and the p33 was not detectable by Western immunoblot in the ultracentrifugal supernatant of the p63-SRSV suspension. These results suggest that the p33 is neither a definitive subunit of p63 nor disintegrated component derived from the p63-SRSV but a novel polypeptide of SRSV. Immune electron microscopy and Western immunoblot analyses indicated that p63- and p33-SRSVs may share an antigenic determinant(s). 相似文献
7.
Absence of surface-associated microorganisms in adult oysters (Crassostrea gigas). 总被引:1,自引:0,他引:1
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Healthy, actively feeding intertidal oysters were removed from an estuarine environment (Pipeclay Lagoon, Tasmania). The epithelial surfaces of various organs of the mantle cavity and alimentary tract were explored by scanning and transmission electron microscopy. All epithelial tissues examined were ciliated, and nearly all were partly covered with secreted mucus. However, microorganisms were seen rarely in the adhesive mucus and never attached to the epithelium. Electron microscopy also failed to demonstrate a surface microflora in emersed oysters which had been incubated at 5 to 25 degrees C for 6 or 24 h. The absence of an internal surface microflora did not vary on a seasonal basis. In laboratory experiments, oysters were allowed to filter feed from seawater containing diverse types of marine bacteria at concentrations of 10(3) to 10(7)/mL. However, no surface microflora could be found within actively feeding oysters or in emersed animals incubated at 20 degrees C for 6 or 24 h. In contrast, surface-associated microorganisms were detected readily by scanning electron microscopy on the external shell of healthy oysters and on various internal tissues in spoiled oysters. It is suggested that the major mechanisms restricting microbial growth within oysters are ciliary movement and mucus secretion. 相似文献
8.
E Kjeldsberg 《Acta pathologica et microbiologica Scandinavica. Section B, Microbiology》1977,(5):351-354
Faecal samples from 238 patients with gastroenteritis were examined by direct electron microscopy using grids with thin carbon film. Of these samples 18 were found to contain Norwalk agent-like particles, calicivirus, astrovirus and parvovirus-like particles. Immune electron microscopy was performed on a serum pair and faeces from one of the patients with astrovirus. An antibody response was demonstrated, suggesting that the virus was the etiological agent of the infection. 相似文献
9.
Ruiz M Darriba S Rodríguez R Iglesias D Lee R López C 《Diseases of aquatic organisms》2011,94(3):239-241
During a histological survey of razor clam Ensis arcuatus (Jeffreys, 1865) from Galicia (NW Spain), basophilic inclusion bodies were observed in epithelial cells of the digestive gland. Transmission electron microscopy revealed the intranuclear position of these inclusions containing viral particles with icosahedral symmetry. Size and symmetry of these unenveloped virus particles suggest similarities to the families Papillomaviridae and Polyomaviridae which have been described as causing a viral gametocytic hypertrophy in oysters Crassostrea virginica and C. gigas. This is the first report of viral particles in E. arcuatus. 相似文献
10.
Yongxin Yu Hui Cai Linghao Hu Rongwei Lei Yingjie Pan Shuling Yan Yongjie Wang 《Applied and environmental microbiology》2015,81(21):7615-7624
Noroviruses (NoVs) are a leading cause of epidemic and sporadic cases of acute gastroenteritis worldwide. Oysters are well recognized as the main vectors of environmentally transmitted NoVs, and disease outbreaks linked to oyster consumption have been commonly observed. Here, to quantify the genetic diversity, temporal distribution, and circulation of oyster-related NoVs on a global scale, 1,077 oyster-related NoV sequences deposited from 1983 to 2014 were downloaded from both NCBI GenBank and the NoroNet outbreak database and were then screened for quality control. A total of 665 sequences with reliable information were obtained and were subsequently subjected to genotyping and phylogenetic analyses. The results indicated that the majority of oyster-related NoV sequences were obtained from coastal countries and regions and that the numbers of sequences in these regions were unevenly distributed. Moreover, >80% of human NoV genotypes were detected in oyster samples or oyster-related outbreaks. A higher proportion of genogroup I (GI) (34%) was observed for oyster-related sequences than for non-oyster-related outbreaks, where GII strains dominated with an overwhelming majority of >90%, indicating that the prevalences of GI and GII are different in humans and oysters. In addition, a related convergence of the circulation trend was found between oyster-related NoV sequences and human pandemic outbreaks. This suggests that oysters not only act as a vector of NoV through environmental transmission but also serve as an important reservoir of human NoVs. These results highlight the importance of oysters in the persistence and transmission of human NoVs in the environment and have important implications for the surveillance of human NoVs in oyster samples. 相似文献
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Our study has been aimed at demonstrating the main role of viruses in the aetiology of acute gastroenteritis in children less
than 5 years old and at pointing out the diagnostic potential of electron microscopy in the diagnosis of viral gastroenteritis.
A prospective study was conducted to analyse the aetiology of diarrhoeal diseases in children less than 5 years of age admitted
to the Department of Infectious Diseases between September 2006 and December 2008. All children were tested by faecal culture,
latex agglutination and electron microscopy. A total of 832 children were included in the study. An aetiological agent was
detected in 788 children (94.6 %). A bacterial aetiology was found in 22 (2.6 %) children and bacterial–viral co-infection
was found in 146 (17.6 %) patients. The most frequent causative agents of gastroenteritis in children were viruses, which
were detected in 620 (74.5 %) patients. The main causes of viral gastroenteritis were rotaviruses (detected in 410 children),
followed by caliciviruses (42), coronaviruses (28), adenoviruses (19) and astroviruses (14). Dual viral infections were detected
in 107 children, with rotavirus–calicivirus co-infection being the most common. Electron microscopy proved to be a more sensitive
method in comparison with the latex agglutination test for the diagnosis of rotaviruses and adenoviruses. The major role of
viruses in diarrhoeal diseases among children under 5 years of age in the Czech Republic has been confirmed. The diagnostic
potential of electron microscopy, particularly in small outbreaks of gastroenteritis, was clearly shown. 相似文献
13.
High density lipoproteins (HDL) from 14 patients with obstructive jaundice were examined by gradient gel electrophoresis to determine the effect of obstruction on particle size distribution. HDL from 7 of these patients were fractionated by gel permeation chromatography and further characterized by electron microscopy, SDS gel electrophoresis, apolipoprotein A-I and apolipoprotein A-II immunoturbidimetry, and analysis of chemical composition. In addition, lecithin:cholesterol acyltransferase (LCAT) activity was measured and correlated with plasma apolipoprotein A-I concentration and particle size distribution. HDL were abnormal in all patients regardless of severity, cause, or duration of obstruction. The major HDL subfraction in normal subjects, HDL3a (radius 4.1-4.3 nm) was either absent or considerably diminished, and HDL2b (radius 5.3 nm) was also frequently absent. Very small particles comparable in size to normal HDL3c (radius 3.8 nm) were prominent. In patients with a bilirubin concentration greater than 250 mumol/l, normal HDL had totally disappeared and were replaced by large discoidal particles of radius 8.5 nm and small spherical particles of radius 3.6-3.7 nm. Both populations of particles were markedly depleted of cholesteryl ester and enriched in free cholesterol and phospholipid. The discoidal particles were rich in apolipoproteins E, A-I, A-II, and C, while the small spherical particles contained predominantly apolipoprotein A-I. LCAT activity was diminished in all subjects to 8-54% of normal, and was strongly positively correlated (r = 0.91 P less than 0.05) with plasma apolipoprotein A-I levels. 相似文献
14.
Detection of single microtubules in living cells: particle transport can occur in both directions along the same microtubule 总被引:13,自引:9,他引:4
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《The Journal of cell biology》1984,99(5):1785-1793
Video-enhanced contrast/differential interference-contrast microscopy was used in conjunction with whole mount electron microscopy to study particle transport along linear elements in fibroblasts. Keratocytes from the corneal stroma of Rana pipiens were grown on gold indicator grids and examined with video microscopy. Video records were taken of the linear elements and associated particle transport until lysis and/or fixation of the cells was completed. The preparations were then processed for whole mount electron microscopy. By combining these two methods, we demonstrated that linear elements detected in the living cell could be identified as single microtubules, and that filaments as small as 10 nm could be detected in lysed and fixed cells. The visibility of different cytoplasmic structures changed after lysis with many more cellular components becoming visible. Microtubules became more difficult to detect after lysis while bundles of microfilaments became more prominent. All particle translocations were observed to take place along linear elements composed of one or more microtubules. Furthermore, particles were observed to translocate in one or both directions on the same microtubule. 相似文献
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Rickettsia-like organism associated with tremor disease and mortality of the Chinese mitten crab Eriocheir sinensis 总被引:4,自引:0,他引:4
We report the discovery of a rickettsia-like organism (RLO) in cultured freshwater Chinese mitten crab Eriocheir sinensis. The RLO caused tremor disease and was apparently responsible for a mass mortality (30 to 90%) in 2 provinces in southeast China. Moribund crabs were investigated from different districts during outbreaks in 1999 and 2000. With electron microscopy, 3 different pathogens were detected in moribund crabs: a rickettsia-like organism (RLO), virus-like particles (VLP) and a microsporidian-like protozoan (MLP). Based on the high prevalence, infection intensity and cytopathological signs, the RLO was considered to be the probable cause of the high mortality. Both VLP and MLP occurred at low prevalences and were considered secondary infections. The RLO was 0.22 to 0.35 microm in diameter, granular or clavate, bounded by a cell wall and membrane, and possessed no nucleus but a nucleoid was present. When dividing, RLOs occurred in irregular shapes, such as dumbbells, awls, and crescents. The RLOs exhibited a predilection for muscle and connective tissues and were probably transported to various tissues and organs by hemocytes. 相似文献
17.
Celia Vazquez-Boucard Cristina Escobedo-Fregoso Ma. de Jesus Duran-Avelar César Marcial Escobedo-Bonilla 《Journal of invertebrate pathology》2010,104(3):245-247
Oysters Crassostrea gigas were placed at water supply canals of three shrimp farms in Guasave, Mexico where WSSV outbreaks occur. Animals were sampled through April-August and September-December to detect WSSV DNA.By using three different PCR protocols, only oysters from a farm undergoing a WSSV outbreak were found WSSV-positive in gills and digestive gland. Two WSSV amplicons were sequenced and they corresponded over 99% to WSSV genome segments. Results showed that oysters can capture WSSV particles suspended in water. Susceptibility of oysters to WSSV infection and their role as a carrier remain to be determined. 相似文献
18.
Puskás LG Tiszlavicz L Rázga Z Torday LL Krenács T Papp JG 《Acta biologica Hungarica》2005,56(3-4):233-245
Recent and historical evidence is consistent with the view that atherosclerosis is an infectious disease or microbial toxicosis impacted by genetics and behavior. Because small bacterial-like particles, also known as nanobacteria have been detected in kidney stones, kidney and liver cyst fluids, and can form a calcium apatite coat we posited that this agent is present in calcified human atherosclerotic plaques. Carotid and aortic atherosclerotic plaques and blood samples collected at autopsy were examined for nanobacteria-like structures by light microscopy (hematoxylin-eosin and a calcium-specific von Kossa staining), immuno-gold labeling for transmission electron microscopy (TEM) for specific nanobacterial antigens, and propagation from homogenized, filtered specimens in culture medium. Nanobacterial antigens were identified in situ by immuno-TEM in 9 of 14 plaque specimens, but none of the normal carotid or aortic tissue (5 specimens). Nanobacteria-like particles were propagated from 26 of 42 sclerotic aorta and carotid samples and were confirmed by dot immunoblot, light microscopy and TEM. [3H]L-aspartic acid was incorporated into high molecular weight compounds of demineralized particles. PCR amplification of 16S rDNA sequences from the particles was unsuccessful by traditional protocols. Identification of nanobacteria-like particles at the lesion supports, but does not by itself prove the hypothesis that these agents contribute to the pathogenesis of atherosclerosis, especially vascular calcifications. 相似文献
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Takeshi Minami Yuko Okazaki Hisanao Komiya Yoshitaka Horiuchi Toru Inoue Yuya Yamada Hisako Fushimi 《Biological trace element research》1995,49(1):67-73
Calcification occurred in the kidney of streptozotocin (STZ)-induced diabetic rats fed a low-zinc diet. The deposits were
stained by the von Kossa method and were detected intracellularly in the tubular cells, mainly in the cortico-medullar region.
The deposits were found to be a heterogenous substance on electron microscopy. There were various sizes of deposits, and the
surfactant was very much distorted. Many deposits grew up to bind small particles, and the core-like substance was observed
in the center of the deposit. The component of the deposit was analyzed by an X-ray microanalyzer, and was found to be calcium
and phosphorus. The ratio of calcium to phosphorus was 2.159, which coincided with the ratio of standard hydroxyapatite. From
these observations, the deposit is believed to be hydroxyapatite. It is thought that the core is formed at first, many particles
are then bound to the core, and deposits grow up. 相似文献