• 제목/요약/키워드: Cytoplasmic inclusion

검색결과 39건 처리시간 0.023초

Ultrastructural Changes in Midgut of CPV infected Tropical Tasar Silkworm, Antheraea mylitta (D) (Lepidoptera : Saturniidae)

  • Barsagade, Deepak Deewaji;Kadwey, Mangala Nimbaji
    • International Journal of Industrial Entomology and Biomaterials
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    • 제21권1호
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    • pp.117-125
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    • 2010
  • The tropical tasar silkworms, Antheraea mylitta (D) produce famous silk 'Kosa' in central part of India. Due to outdoor rearing it became susceptible to viral infection including cytoplasmic polyhedrosis virus (CPV). The common mode of entry of cytoplasmic polyhedrosis virus is per os and cause gresserie disease to the larvae. Histopathological studies elucidated the insect CPV virus produces infective polyhedral inclusion bodies (PIBs) in the midgut cell cytoplasm of virus infected fifth instar larvae. The PIBs multiply enormously in the cytoplasm without invading the nucleus. Ultrastructural studies confirmed the pathological effects of CPV on in midgut cell cytoplasm. The multiplication of polyhedral inclusion bodies took place into the vacuoles and form virogenic stromata in the cytoplasm of cells. However, the encapsulations of polyhedral inclusion bodies into the polyhedrin protein occurred and polyhedra were released into the lumen. At the late stage of infection, cells showed the regressed cytoplasmic organelles with large vacuoles and elongated mitochondria. Hence, the horizontal transmission of CPV causing the midgut cells disintegration in the tasar silkworm, Antheraea mylitta (D) confirmed during infection.

Poxvirus 감염(感染)에 있어서의 Virus-숙주세포(宿主細胞)의 상호관계(相互關係) 1. Cowpox Virus-FL 세포계(細胞系)의 세포화학적(細胞化學的) Autoradiography 및 세포면역학적해석(細胞免疫學的解析) (Studies on Host-Virus Interaction of Poxviruses 1. Cytochemical, Autoradiographic and Immunocytological Analysis in Cowpox Virus-FL Cell System)

  • 김우호
    • 대한수의학회지
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    • 제15권1호
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    • pp.57-67
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    • 1975
  • The poxvirus group is considered to be a typical cytoplasmic inclusion forming virus. Every poxvirus has been reported to produce only one kind of inclusion in the infected tissues. A vague concept that inclusions of poxviruses are eosinophilic or acidophilic has prevailed. Although many papers and theories about the nature of the inclusion have been presented, most of them are not quite convincing on the point of the relations with virus multiplication, and an analysis of papers published showed that there seem to be many discrepancies in the descriptions of the nature of the poxvirus inclusions. Comparative studies on host-virus interaction with cowpox, orf, swinepox and fowlpox viruses which selected from each Group (I-IV) of poxviruses were performed from the morphological and virological standpoints. At first, in cowpox virus-FL cell system, as a comparative model, cytoplasmic inclusion, nucleic acid metabolism by autoradiography and detection of viral antigen by immunofluorescence were studied and obtained the results as follows: 1. The focus-like cytopathic effect (CPE) at early stage developed to entire culture at terminal stage of infection, and also the developing status of CPE was correlated to viral doses for inoculation. Two kinds of cytoplasmic inclusions which named A and B type were easily observed by Giemsa, hematoxylin-eosin (H & E) and May-Greenwald Giemsa (MGG) stainings in the infected cells. The B type inclusions were formed at early stage of infection and the A type inclusions were produced subsequently the B type formation. The B type which common type inclusion in poxviruses was a small compact or aggregate at early stage and developed to a large diffuse body at terminal stage of infection. On the other hand, the A type inclusion which depend upon the kind of virus was appeared as round and discrete shape, and its size and number was increased gradually during the culture period. It was characteristic to form distinct halos around the both types of inclusions in acid fixed, H & E stained preparations of infected cultures. The B type inclusion was always positive in Feulgen reaction and showed as DNA containing body but the A type inclusion was not. 2. In the relationship between inclusion and DNA metabolism of infected cells by the qualitative autoradiography using 3H-thymidine, the appearance of silver grains was coincided with B type inclusion but not with A type inclusion. This showed that the DNA synthesis was proceeded in all B type inclusions except those in the terminal stage with a diffuse form. This suggested that the B type inclusions are only sites of DNA synthesis and this was proceeded after the cell infection independently. The activity of DNA synthesis of the inclusions was nearly the same as that of the nucleic of normal cells and non-inclusion bearing cells. and non-inclusion bearing cells. Regardless of the size of the degree of DNA synthesis of the B type inclusion, inclusion bearing cells all showed remarkable suppression of nuclear DNA synthesis. 3. By the direct fluorescent antibody technique viral antigen in infected cells was detected. The B type inclusions have been proved to contain a great deal of viral antigen, whereas the basic substance of A type inclusion did not show antigenicity except the round edge. It was suggested that the round edge fluorescence might be caused by the glare of cytoplasmic viral antigen which pushed out and concentrated by the A type inclusion development. 4. Hemorrhagic red pock formations on chorioallantoic membrane of embryonated chicken egg had proved the characteristic of used viral strain. 5. By the above studies on the nature of two types of inclusions and the role they play in virus multiplication, it was concluded that the B type inclusion must be the site of the synthesis of viral DNA and protein as well as the site of the virus.

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A Cytoplasmic Polyhedrosis Virus Isolated from the Pine Processionary Caterpillar, Thaumetopoea pityocampa

  • Ince, Ikbal Agah;Demir, Ismail;Demirbag, Zihni;Nalcacioglu, Remziye
    • Journal of Microbiology and Biotechnology
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    • 제17권4호
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    • pp.632-637
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    • 2007
  • A cytoplasmic polyhedrosis virus (CPV) was isolated from the larvae of Thaumetopoea pityocampa and shown to cause an infection of midgut cells. This viral infection revealed several important diagnostic symptoms, including discoloration of the posterior midgut, reduced feeding, and extended development time of the larvae. The virus infection is lethal to Thaumetopoea pityocampa, and with the increasing doses kills the larvae within 4-5 days post infection. Electron microscopy studies showed typical cytoplasmic polyhedral inclusion bodies that are icosahedral, and ranged from 2.4 to $5.3{\mu}m$ in diameter. Electrophoretic analysis of the RNA genome showed that the virus has a genome composed of 10 equimolar RNA segments with the sizes of 3,907, 3,716, 3,628, 3,249, 2,726, 1,914, 1,815, 1,256, 1,058, and 899 bp, respectively. Based on morphology and nucleic acid analysis, this virus was named Thaumetopoea pityocampa cytoplasmic polyhedrosis virus (TpCPV), and belongs to the genus Cypovirus, family Reoviridae.

Preparation of Diphtheria Toxin A Chain from Escherichia coli

  • Lee, Jong-Soo;Yoon, Kyoung-Bum;Park, Jong-Won;Choi, Suk-Jung
    • BMB Reports
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    • 제30권2호
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    • pp.144-149
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    • 1997
  • An expression vector was constructed containing the gene encoding diphtheria toxin A (DTA) which was placed after a T7 promoter. Cytoplasmic expression of the DTA gene resulted in the formation of an insoluble inclusion body. The inclusion body was collected after the complete lysis of the cell, and subsequent washing with 0.1% Triton X-100 released 16~30% of DTA protein from the inclusion body along with other contaminating proteins. The released DTA protein was purified by dialysis. The remaining pellet was dissolved in 8 M urea containing 5% ${\beta}-mercaptoethanol$, and the denatured DTA was renatured by the dilution-dialysis method. The total yield was 35%, and about 5 mg DTA was obtained from 1 L culture. The DTA protein has a free sulfhydryl group exposed to the protein surface, and was shown to have a tendency to dimerize through disulfide formation in the absence of ${\beta}-mercaptoethanol$. The utility of the sulfhydryl group was tested for the construction of recombinant toxins.

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Fermentation and Purification of LacZ-Fused Single Chain Insulin Precursor for($B^{30}$-Homoserine) Human Insulin

  • SeungYup Lee;Jeo
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제1권1호
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    • pp.9-12
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    • 1996
  • In order to produce the single chain precursor of a novel human insulin analogue, (B30-Homoserine) insulin, the fermentative behaviors of Escherichia coli JM103 were studied, which harbors pKBA plasmid carrying a hybrid gene in which the gene for a single chain precursor was fused with lacZ gene under tac promoter. The maximal induction of gene expression was achieved when more than 0.05 mM of isopropyl-$\beta$-D-thiogalactopyranoside(IPTG) was supplemented to fermentation medium after 4 h cultivation of E. coli, and followed by longer than 2-h fermentation. The hybrid protein of the single chain insulin precursor was isolated from cytoplasmic inclusion bodies by dissolving in 8M urea solution, and purified through DEAE-Sephacel and Sephadex G-200 column chromatographies with a recovery of 35%. The finally purified hybrid protein showed a single band on sodium dodecyl sulfate-polyacrylamide gel.

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수컷생쥐의 Leydig Cell 미세구조에 대한 Chlorambucil의 영향 (Effect of Chlorambucil on the Ultrastructure of Leydig Cell in Male Mouse)

  • 김덕훈;박원학
    • Applied Microscopy
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    • 제18권2호
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    • pp.21-33
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    • 1988
  • The purpose of this study was to investigate the effect of chlorambucil on the mouse Leydig cell by electron microscopy. Chlorambucil suspended in the 0.5N sodium bicarbonate(pH 8.0) was injected I.P.(intraperitoneal) at a dosage of level 20mg/kg for 1 weeks, 3 weeks and 5 weeks, respectively. The results obtained from this experiment are as follows: 1. One week after the administration of chlorambucil, there was an increase in heterochromatin, swelling and cristae disruption in some mitochondria, mild vacuolation between cells and the occurrence of membrane bound inclusions in some nuclei. 2. After 3 weeks, smooth endoplasmic reticulum dilations, cytoplasmic vacuolation, mitochondrial swelling, inner mitochondrial cristae disruption, membranous whorls, and intranuclear inclusions were observed in the treated cells. 3. After 5 weeks of treatment, most mitochondria were swollen and their membranes were severely disrupted. Further, smooth endoplasmic reticulum dilations and vacuolation of the cytoplasm were apparent in the treated Leydig cells. In addition numerous membranous whorls and intranuclear inclusion bodies were present. The nuclei displayed invaginatons of the nuclear membrane and large clumps of heterochromatin. From these results it is concluded the longer the duration of chlorambucil administration, the greater the degeneration of the nucleus and cytoplasmic organelles.

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설사증 이환견(罹患犬)으로 부터 분리한 canine parvovirus의 성상에 관한 연구 (Biological and physicochemical properties of canine parvovirus isolated from the dogs with diarrhea)

  • 최해연;전무형;박성국
    • 대한수의학회지
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    • 제31권3호
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    • pp.295-302
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    • 1991
  • From 1988 to 1989, 8 strains of canine parvovirus-2(CPV-2) were isolated from the fecal specimens from the dogs that were clinically diagnosed as canine parvoviral enteritis in the veterinary hospitals located in the regions of Taejeon and Chungbuk province. The biological and physicochemical properties for the isolates were studied. Among 62 fecal samples collected from the dogs with enteric diseases, 24(38.7%) showed the haemagglutinating activity to porcine erythrocyte ranging from 16 to 16,384 of HA titers. In cytopathological studies with CRFK cells, intranuclear inclusion bodies were observed in all of eight specimens with the high HA titer over 1,000, of which three specimens showed cytoplasmic inclusions concurrently with the intranuclear inclusion bodies. It was found that the isolates revealed the highest haemagglutinating activity with porcine erythrocytes and the relatively lower haemagglutination titers with the erythrocytes from cat and rabbit. None of erythrocytes from the other animals reacted with the isolates. By the cross-haemagglutination inhibition test for the isolates with the reference viruses and sera, the isolates were evidently identified as the strains of CPV-2. In physicochemical property test, the isolates were stable in lipid solvent, pH and heat treatment at $56^{\circ}C$ for 30 min, and showed the virus particle size less than 25 nm, containing a DNA genome.

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In Vitro Formation of Active Carboxypeptidase Y from Pro-Carboxypeptidase Y Inclusion Bodies by Fed-Batch Operation

  • Hahm, Moon-Sun;Chung, Bong-Hyun
    • Journal of Microbiology and Biotechnology
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    • 제11권5호
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    • pp.887-889
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    • 2001
  • The gene encoding yeast pro-carboxypeptidase Y (pro-CPY) has been cloned and expressed in Escherichia coli. Most of the expressed pro-CPY was accumulated as cytoplasmic insoluble aggregates. In our previous study, active CPY was obtained by renaturation of entirely denatured pro-CPY followed by in vitro proteolytic processing with proteinase K along with the activation process. The same refolding process was performed to produce an active CPY from pro-CPY inclusion bodies with renaturation buffers containing proteinase K at different concentrations. The refolding efficiency decreased from $25\%\;to\;2\%$ in the renaturation buffers containing proteinase K at concentrations of $60{\mu}g/ml\;and\;0.6{\mu}g/mi$, respectively. In an attempt to increase the refolding efficiency with a lesser amount of proteinase K, a novel fed-batch refolding process was developed. In a fed-batch refolding, 99 ml of the renaturation buffer containing pro-CPY was gradually added into 1 ml of the renaturation buffer containing $60{\mu}g/ml$ of proteinase K to give a final proteinase K concentration of $0.6{\mu}g/ml$. The fed-batch refolding process resulted in a refolding efficiency of $18\%$, which corresponded to a 9-fold increase over that ($2\%$) in the batch process.

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