Plant Tumors of Viral Origin

Author(s):  
L. M. Black
Keyword(s):  
Author(s):  
A. E. Ritchie

The cause of bluecomb disease in turkeys is unknown. Filtration of infective intestinal contents suggests a viral origin. To date, it has not been possible to isolate the etiologic agent in various cell cultures. The purpose of this work was to characterize as many virus-like entities as were recognizable in intestines of both healthy and bluecomb-infected turkeys. By a comparison of the viral populations it was hoped that some insight might be gained into the cause of this disease. Studies of turkey hemorraghic enteritis by Gross and Moore (Avian Dis. 11: 296-307, 1967) have suggested that a bacteriophage-host cell interaction may bear some causal relationship to that disease.


Author(s):  
Anthony Demsey ◽  
Christopher W. Stackpole

The murine leukemia viruses are type-C oncornaviruses, and their release from the host cell involves a “budding” process in which the newly-forming, RNA-containing virus core becomes enveloped by modified cell surface membrane. Previous studies revealed that the released virions possess a dense array of 10 nm globular projections (“knobs”) on this envelope surface, and that these knobs contain a 70, 000 MW glycoprotein (gp70) of viral origin. Taking advantage of this distinctive structural formation, we have developed a procedure for freeze-drying and replication of intact cells which reveals surface detail superior to other surface replica techniques, and sufficient to detect even early stages of virus budding by localized aggregation of these knobs on the cell surface.Briefly, cells growing in monolayer are seeded onto round glass coverslips 10-12 mm in diameter. After a period of growth, cells are fixed in situ for one hour, usually with 1% OsO4 in 0. 1 M cacodylate buffer, and rinsed in distilled water.


Author(s):  
S. Fujinaga ◽  
K. Maruyama ◽  
C.W. Williams ◽  
K. Sekhri ◽  
L. Dmochowski

Yumoto and Dmochowski (Cancer Res.27, 2098 (1967)) reported the presence of mature and immature type C leukemia virus particles in leukemic organs and tissues such as lymph nodes, spleen, thymus, liver, and kidneys of SJL/J strain mice with Hodgki's-like disease or reticulum cell neoplasm (type B). In an attempt to ascertain the possibility that this neoplasia may be of viral origin, experiments with induction and transmission of this neoplasm were carried out using cell-free extracts of leukemic organs from an SJL/J strain mouse with spontaneous disease.It has been possible to induce the disease in low-leukemia BALB/c and C3HZB strain mice and serially transfer the neoplasia by cell-free extracts of leukemic organs of these mice. Histological examination revealed the neoplasia to be of either reticulum cell-type A or type B. Serial transfer is now in its fifth passage. In addition leukemic spleen from another SJL/J strain mouse with spontaneous reticulum cell neoplasm (type A) was set up in tissue culture and is now in its 141st serial passage in vitro. Preliminary results indicate that cell-free material of 39th tissue culture passage can reproduce neoplasia in BALB/c mice.


2016 ◽  
Vol 64 (1) ◽  
pp. 79-82
Author(s):  
Maria Carolina de Lima Jacy MONTEIRO ◽  
Cristiane FURUSE ◽  
Larissa Cunha CÊ ◽  
Alexandre Freitas SANTANA ◽  
Vera Cavalcanti de ARAÚJO

ABSTRACT Verruciform xanthoma is a rare, benign lesion, with a papillary aspect, asymptomatic, sessile, white colored, and well-demarcated, that occurs in the gingiva and alveolar mucosa. The histopathological aspect is characterized by the presence of macrophages with foam cytoplasm (xanthoma cells) confined to the soft papillary tissue. The etiology and pathogenic mechanisms are unknown, although some hypothesis, such as local trauma or viral origin have been suggested. The aim of this article was report a clinical case of verruciform xanthoma located in the gingiva showing the clinical and histopathological aspects.


1987 ◽  
Vol 32 (5) ◽  
pp. 149-150
Author(s):  
J. Hamilton ◽  
R.A. Sharp ◽  
J. M. Anderson ◽  
M. R. Kerr

Inflammatory polymyositis can be precipitated by acute febrile illness of viral origin1, but similar association with pyogenic bacterial illness is not recognised. We describe two cases in which recovery from staphylococcal septicaemia was complicated by a widespread inflammatory myopathy.


Author(s):  
Georg Seifert ◽  
Petra Funk ◽  
Thorsten Reineke ◽  
Walter Lehmacher

Abstract Objective Acute tonsillopharyngitis (ATP) is a common, seasonal infection of predominantly viral origin. Management is aimed at shortening the course of the disease and restoring the comfort of the patient. We performed a meta-analysis to investigate whether treatment with the Pelargonium sidoides extract EPs 7630 reduces the use of antipyretic comedication (i.e., acetaminophen) in children suffering from ATP. Methods Studies were identified from clinical trial registries and medical literature. Randomized, placebo-controlled, clinical trials investigating EPs 7630 in children with ATP and reporting the coadministration of paracetamol were eligible. Based on the raw data of eligible trials, we analyzed cumulative paracetamol use, as well as the ability to attend school at the end of treatment. Three trials including a total of 345 children aged 6 to 10 years and suffering from non-β-hemolytic streptococcal ATP were identified and eligible. Children were administered EPs 7630 or placebo for 6 days. Results Compared with placebo, EPs 7630 reduced the cumulative paracetamol dose by an average of 449 mg (95% confidence interval [CI]: 252–646 mg; p < 0.001). A total of 19.1% (EPs 7630) and 71.5% (placebo) of children were still unable to attend school at the end of the treatment (risk ratio = 0.28; 95% CI: 0.16–0.48; p < 0.001). Conclusion Our meta-analysis demonstrates that EPs 7630 reduced the use of antipyretic comedication and accelerated recovery.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Minkyung Choi ◽  
Jae-Young Yun ◽  
Jun-Hyuk Kim ◽  
Jin-Soo Kim ◽  
Sang-Tae Kim

AbstractCRISPR/Cas9-mediated genome editing is an important and versatile technology in modern biological research. Recent advancements include base-editing CRISPR tools that enable targeted nucleotide substitutions using a fusion protein comprising a nickase variant of Cas9 and a base deaminase. Improvements in base editing efficiencies and inheritable of edited loci need to be made to make CRISPR a viable system in plants. Here, we report efficiency of cytosine base editors (CBEs) in Arabidopsis thaliana by applying the strong endogenous RPS5a promoter to drive the expression of nickase Cas9 and either rAPOBEC1 from rat (BE3) or the PmCDA1 activation-induced cytidine deaminase from sea lamprey (AIDv2). Compared with the strong heterologous CaMV35S promoter of viral origin, the RPS5a promoter improved CBE efficiency by 32% points with the number of T1 plants showing over 50% conversion ratio when the LFY gene was targeted. CBE induced nonsense mutations in LFY via C-to-T conversion, which resulted in loss-of-function lfy phenotypes; defects in LFY function were associated with the targeted base substitutions. Our data suggest that optimal promoter choice for CBE expression may affect base-editing efficiencies in plants. The results provide a strategy to optimize low-efficiency base editors and demonstrate their applicability for functional assays and trait development in crop research.


1990 ◽  
Vol 10 (1) ◽  
pp. 75-83
Author(s):  
Y Berko-Flint ◽  
S Karby ◽  
D Hassin ◽  
S Lavi

An in vitro system to study carcinogen-induced amplification in simian virus 40 (SV40)-transformed Chinese hamster (CO60) cells is described. SV40 amplification in this system resembled in many aspects the viral overreplication observed in drug-treated CO60 cells. Cytosolic extracts from N-methyl-N'-nitro-N-nitrosoguanidine-treated cells supported de novo DNA synthesis in the presence of excess exogenous T antigen and the SV40-containing plasmid pSVK1. The pattern of viral replication in these extracts was unique, since only the 2.4-kilobase-pair region spanning the origin was overreplicated, whereas distal sequences were not replicated significantly. Extracts from control cells supported only marginal levels of replication. In HeLa extracts, complete SV40 DNA molecules were replicated efficiently. The overreplication of the origin region in CO60 cell extracts was bidirectional and symmetrical. A fraction of the newly synthesized DNA molecules underwent a second round of replication, yielding MboI-sensitive fragments representing the 2.4-kilobase-pair region around the origin. The mechanisms controlling the amplification of the viral origin region, the nature of the cellular factors induced in the carcinogen-treated cells, and their putative association with general drug-induced SOS-like responses are discussed.


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